I have a question for you guys, Will a pre 1987 block that is non roller be able to be converted over to a roller engine? What i was thinking about doing was installing all of the roller components from a friends roller motor onto an older non roller 350 if that is possible, i have a set of L98 heads that i could put on the block, and a used LT4 cam. So is this possible, or are the pre 87 blocks completely different? Let me know guys, thanks

No, it is not possible.

It's not that the early blocks are different; it's the late ones that are "different". The rest of us had all been building roller motors for decades, before the factory got a whiff of it and assigned it to the summer engineering intern, who used it as his sophomore project. The factory's goofy roller system therefore ended up requiring a redesign of the block, the cam, and the timing chain.

You can, however, put the original design roller system into an early block, using what is now referred to as "retrofit" roller lifters. They do not require any modification to anything whatsoever. You'd need those, a set of the correct length push rods for whatever lifters you use (they aren't all the same height), and a cam button.

It doesn't make the slightest difference what heads you use. Any heads will work with either a flat tappet, or a "retrofit" roller, or the factory's stupid roller system.