[Adam331Fastback]

Can you use a 1 piece real main seal on this block? Or it only uses a 2 piece bc ive read that you have to machine the rear cap for it to use the 1 piece??? Anyone heard this?

 

[Trojan Horse]

Can you use a 1 piece real main seal on this block? Or it only uses a 2 piece bc ive read that you have to machine the rear cap for it to use the 1 piece??? Anyone heard this?

For all older blocks you have to have them machined to accept the newer style one piece seals. What year is the block?