The heads are almost identical and the throttle body wouldn't fit on a mustang because i think it's not the same design. The intakes won't work either because of the same reason, the lower intake also is wider. You could use the heads in the future but you'd need to have washers or somethign for the bolts because the head bolts are larger in diameter in the 5.8L., but the heads could be useful. The front timing chain cover is identical, but i don't see why you'd ever need one. I really can't think of much that you could use off of the truck.
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previous name: 84stangLX
'84 Mustang 5.0 LX
my LX
'89 Mustang GT
my GT