just purchased a 98 nascar f150 with the 4.6, manual trans. The engine has over 200 thousand miles and needs head gaskets. Can I transplant a 4.6 from a mustang GT

 

easily

 

Use your truck intake.

 

Your 98 truck is non PI so yes you can use your truck intake on 98 or earlier non PI Mustang engines. If you get a 99 or newer Mustang engine which will be PI then your 98 truck intake is not compatable unless you buy adapter plates and I'm not sure if the adapter plates are still available. PI (power improved) non PI ( non power improved)

 

If you go with a higher power engine, take it easy on the tranny - the M5OD is light duty.