This script will find the selected email message with Spotlight and open it in BBEdit for editing.<p> (Change "BBEdit" to "TextWrangler" to use the free version of BBEdit instead.)

Edit_Email_in_BBEdit.applescript

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# Auth: Christopher Stone <junksieve@thestoneforge.com>
# dCre: 2012-07-18 : 05:51
# dMod: 2013-06-25 : 14:26
# Appl: Mail & BBEdit
# Task: Open selected message's file in BBEdit for editing.
# Deps: Uses only OSX components.
# Test: Lion & Mountain Lion (might work in Snow Leopard but I cannot test).
# Tags: @Applescript, @Mail, @BBEdit, @Edit, @Message
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--» #### { NOTES } ########################################################################
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(*

TO-DO:
  • Fix Spotlight Query.
		+ Do 2nd query if 1st query fails.

*)
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--» HANDLERS
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on REPL(_str, _find, _repl)
	set {oldTIDS, AppleScript's text item delimiters} to {AppleScript's text item delimiters, _find}
	set _str to text items of _str
	set AppleScript's text item delimiters to _repl
	set _str to _str as text
	set AppleScript's text item delimiters to oldTIDS
	return _str
end REPL
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on textToBBEdit(_data)
	if _data starts with "/" then
		try
			set _data to alias POSIX file _data
		end try
	end if
	tell application "BBEdit"
		activate
		if class of _data = alias then
			open _data
		else if class of _data = text then
			set newDoc to make new document with properties {text:_data}
		end if
		set bounds of front window to {303, 44, 1617, 1196}
	end tell
end textToBBEdit

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--» MAIN
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try
	
	set AppleScript's text item delimiters to {""}
	
	tell application "Mail"
		set _sel to selection
		if length of _sel = 1 then
			set _msg to item 1 of _sel
		else
			error "Too many messages selected."
		end if
		# Use account to find mail-folder in attempt to be compatible back to Snow Leopard.
		set acnt1Dir to (account directory of account 1) as string
		set {oldTIDS, AppleScript's text item delimiters} to {AppleScript's text item delimiters, ":"}
		set mailFldrLion to POSIX path of (text items 1 thru -3 of acnt1Dir as string)
		set AppleScript's text item delimiters to oldTIDS
		tell _msg
			set mbxName to name of its mailbox
			set mID to its id
			set mSub to its subject
		end tell
	end tell
	
	# Escape single quotes in subject for spotlight query string.
	if mSub contains "'" then
		set mSub to REPL(mSub, "'", "'\"'\"'")
	end if
	
	# Find email 
	set _cmd to "mdfind -onlyin " & mailFldrLion & " 'kMDItemDisplayName == \"" & mSub & "\"cd && kMDItemFSName == \"" & mID & ".emlx\"cd'"
	
	--» •••• Debug Code ••••
	# textToBBEdit(_cmd)
	# return
	
	set emlFile to do shell script _cmd
	if emlFile ≠ "" then
		textToBBEdit(emlFile)
	else
		error "No message was returned by Spotlight!"
	end if
	
on error e number n
	set e to e & return & return & "Num: " & n
	tell me to set dDlg to display dialog e with title "ERROR!" buttons {"Cancel", "Copy", "OK"} default button "OK"
	if button returned of dDlg = "Copy" then set the clipboard to e
end try

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