SGIII just posted a script in another thread that exports selected emails to a Numbers table. You might try it on one of your emails to see if the content ends up in a cell in a format that you can use. If so, maybe you can make some adjustments to the script for your needs.
set dataLst to {{"SenderAddress", "SenderName", "Date", "Time", "Content"}}
tell application "Mail"
repeat with aMsg in items of (get selection)
tell aMsg
set senderNameAddr to my splitEmail(sender)
set senderAddr to item 2 of senderNameAddr
set senderName to item 1 of senderNameAddr
set msgSubj to subject
set msgDate to date received
set msgTime to time string of msgDate
set msgDate to my dateFormat(date string of msgDate)
set msgContent to content
set msgLst to {senderAddr, senderName, msgDate, msgTime, msgContent}
copy msgLst to dataLst's end
end tell
end repeatend tell
tell application "Numbers"
set newDoc to make new document
tell table 1 of active sheet of newDoc
delete column "A" -- remove default Header Column
set column count to length of item 1 of dataLst
set row count to (length of dataLst)
repeat with i from 1 to length of dataLst
repeat with j from 1 to length of item 1 of dataLst
set value of cell j of row i to item j of item i of dataLst
end repeat
end repeat
end tellend tell
to dateFormat(aDateString) --> yyyy-mm-dd
set {year:y, month:m, day:d} to date aDateString
tell (y * 10000 + m * 100 + d) as string to text 1 thru 4 & "-" & text 5 thru 6 & "-" & text 7 thru 8end dateFormat
to splitEmail(nameAddress)
set text item delimiters to "<"
tell nameAddress
set theName to text item 1
set theAddress to text 1 thru -2 of text item 2
end tell return {theName, theAddress}
end splitEmail