A couple secondary thoughts;
1. I know of one 1986 Pantera that came factory with a 351W with C heads.
2. You could stablize the block by filling the cooling on the bottom of the block with 6000psi grout about 2/3 of the way up ..the bottom of the block dosent generate heat. This stablizes the block. I ran 4 428 Cj this way ..due to thin cylinder walls and it worked for me.
3. Pick any one of the FORD SVO block and they are legal.
Ron
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