They are different engines for the most part. The heads definitely are and certainly aren't interchangble, as no one here has ever swapped any over. I would assume different ports/passages.

Do some searching on here for past threads and Diamante and 3000GT blocks. You may have options there. There were 3.0 DOHC ones, but also some in the 175HP range (IIRC), which would say to me 3.0 SOHC 24V.

Big Truck: 00, 3.5, Endeavor, 5-Spd drive line in hand!
Little Truck: 87, 2.6T I/C, MT, LSDs, Tonneau Top
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