diff --git a/helpers/helpers.js b/helpers/helpers.js
index f407e7ef..d5f0c0b9 100644
--- a/helpers/helpers.js
+++ b/helpers/helpers.js
@@ -404,7 +404,7 @@ module.exports.frontMatterHasTitle =
 module.exports.fixErrors = function fixErrors(input, errors) {
   const lines = input.split(newLineRe);
   // Normalize fixInfo objects
-  const fixInfos = errors.filter((error) => !!error.fixInfo).map((error) => {
+  let fixInfos = errors.filter((error) => !!error.fixInfo).map((error) => {
     const { fixInfo } = error;
     return {
       "lineNumber": fixInfo.lineNumber || error.lineNumber,
@@ -413,14 +413,46 @@ module.exports.fixErrors = function fixErrors(input, errors) {
       "insertText": fixInfo.insertText || ""
     };
   });
-  // Sort bottom-to-top, deletes last, right-to-left, long-to-short
-  fixInfos.sort((a, b) => (
-    (b.lineNumber - a.lineNumber) ||
-    ((a.deleteCount === -1) ? 1 : ((b.deleteCount === -1) ? -1 : 0)) ||
-    (b.editColumn - a.editColumn) ||
-    (b.insertText.length - a.insertText.length)
-  ));
-  // Apply all fixes
+  // Sort bottom-to-top, line-deletes last, right-to-left, long-to-short
+  fixInfos.sort((a, b) => {
+    const aDeletingLine = (a.deleteCount === -1);
+    const bDeletingLine = (b.deleteCount === -1);
+    return (
+      (b.lineNumber - a.lineNumber) ||
+      (aDeletingLine ? 1 : (bDeletingLine ? -1 : 0)) ||
+      (b.editColumn - a.editColumn) ||
+      (b.insertText.length - a.insertText.length)
+    );
+  });
+  // Remove duplicate entries (needed for following collapse step)
+  let lastFixInfo = {};
+  fixInfos = fixInfos.filter((fixInfo) => {
+    const unique = (
+      (fixInfo.lineNumber !== lastFixInfo.lineNumber) ||
+      (fixInfo.editColumn !== lastFixInfo.editColumn) ||
+      (fixInfo.deleteCount !== lastFixInfo.deleteCount) ||
+      (fixInfo.insertText !== lastFixInfo.insertText)
+    );
+    lastFixInfo = fixInfo;
+    return unique;
+  });
+  // Collapse insert/no-delete and no-insert/delete for same line/column
+  lastFixInfo = {};
+  fixInfos.forEach((fixInfo) => {
+    if (
+      (fixInfo.lineNumber === lastFixInfo.lineNumber) &&
+      (fixInfo.editColumn === lastFixInfo.editColumn) &&
+      !fixInfo.insertText &&
+      (fixInfo.deleteCount > 0) &&
+      lastFixInfo.insertText &&
+      !lastFixInfo.deleteCount) {
+      fixInfo.insertText = lastFixInfo.insertText;
+      lastFixInfo.lineNumber = 0;
+    }
+    lastFixInfo = fixInfo;
+  });
+  fixInfos = fixInfos.filter((fixInfo) => fixInfo.lineNumber);
+  // Apply all (remaining/updated) fixes
   let lastLineIndex = -1;
   let lastEditIndex = -1;
   fixInfos.forEach((fixInfo) => {
diff --git a/lib/md006.js b/lib/md006.js
index 2117ffaa..673bb1f0 100644
--- a/lib/md006.js
+++ b/lib/md006.js
@@ -13,10 +13,19 @@ module.exports = {
   "tags": [ "bullet", "ul", "indentation" ],
   "function": function MD006(params, onError) {
     flattenedLists().forEach((list) => {
-      if (list.unordered && !list.nesting) {
-        addErrorDetailIf(onError, list.open.lineNumber,
-          0, list.indent, null, null,
-          rangeFromRegExp(list.open.line, listItemMarkerRe));
+      if (list.unordered && !list.nesting && (list.indent !== 0)) {
+        const { lineNumber, line } = list.open;
+        addErrorDetailIf(
+          onError,
+          lineNumber,
+          0,
+          list.indent,
+          null,
+          null,
+          rangeFromRegExp(line, listItemMarkerRe),
+          {
+            "deleteCount": line.length - line.trimLeft().length
+          });
       }
     });
   }
diff --git a/lib/md023.js b/lib/md023.js
index bf29d513..92d4c00f 100644
--- a/lib/md023.js
+++ b/lib/md023.js
@@ -2,8 +2,7 @@
 
 "use strict";
 
-const { addErrorContext, filterTokens, rangeFromRegExp } =
-  require("../helpers");
+const { addErrorContext, filterTokens } = require("../helpers");
 
 const spaceBeforeHeadingRe = /^((?:\s+)|(?:[>\s]+\s\s))[^>\s]/;
 
@@ -13,9 +12,26 @@ module.exports = {
   "tags": [ "headings", "headers", "spaces" ],
   "function": function MD023(params, onError) {
     filterTokens(params, "heading_open", function forToken(token) {
-      if (spaceBeforeHeadingRe.test(token.line)) {
-        addErrorContext(onError, token.lineNumber, token.line, null,
-          null, rangeFromRegExp(token.line, spaceBeforeHeadingRe));
+      const { lineNumber, line } = token;
+      const match = line.match(spaceBeforeHeadingRe);
+      if (match) {
+        const [ prefixAndFirstChar, prefix ] = match;
+        let deleteCount = prefix.length;
+        const prefixLengthNoSpace = prefix.trimRight().length;
+        if (prefixLengthNoSpace) {
+          deleteCount -= prefixLengthNoSpace - 1;
+        }
+        addErrorContext(
+          onError,
+          lineNumber,
+          line,
+          null,
+          null,
+          [ 1, prefixAndFirstChar.length ],
+          {
+            "editColumn": prefixLengthNoSpace + 1,
+            "deleteCount": deleteCount
+          });
       }
     });
   }
diff --git a/test/lists-with-nesting.md b/test/lists-with-nesting.md
index defdf813..5c89a8c9 100644
--- a/test/lists-with-nesting.md
+++ b/test/lists-with-nesting.md
@@ -16,13 +16,11 @@
 
 - one {MD032}
  1. two {MD032}
- 1. three {MD032}
-- four {MD032}
+- three {MD032}
 
 1. one {MD032}
   - two {MD006} {MD032}
-  - three {MD032}
-1. four {MD032}
+1. three {MD032}
 
 ## Correct nesting, same type
 
diff --git a/test/markdownlint-test.js b/test/markdownlint-test.js
index 537d5c7a..437e5a6a 100644
--- a/test/markdownlint-test.js
+++ b/test/markdownlint-test.js
@@ -1898,7 +1898,7 @@ module.exports.forEachInlineCodeSpan = function forEachInlineCodeSpan(test) {
 };
 
 module.exports.fixErrors = function fixErrors(test) {
-  test.expect(23);
+  test.expect(24);
   const testCases = [
     [
       "Hello world.",
@@ -2221,6 +2221,20 @@ module.exports.fixErrors = function fixErrors(test) {
       ],
       "Hello wld"
     ],
+    [
+      "Hello world",
+      [
+        {
+          "fixInfo": {
+            "lineNumber": 1,
+            "editColumn": 7,
+            "deleteCount": 1,
+            "insertText": "z"
+          }
+        }
+      ],
+      "Hello zorld"
+    ],
     [
       "Hello world",
       [
@@ -2239,7 +2253,7 @@ module.exports.fixErrors = function fixErrors(test) {
           }
         }
       ],
-      "Hello zworld"
+      "Hello zorld"
     ],
     [
       "Hello world",
@@ -2259,7 +2273,7 @@ module.exports.fixErrors = function fixErrors(test) {
           }
         }
       ],
-      "Hello zworld"
+      "Hello zorld"
     ]
   ];
   testCases.forEach((testCase) => {