The early LT1s only have one serious problem I’m aware of. About 80k to 100k miles the waterpump goes and it kills the opti spark distributor. They’re mounted on the same spindle.
92-96 are the same basic car as 84-91, so no big issues.
One of the reasons I’m considering having it as a second car. I can’t work on anything and I don’t want to be stranded by a breakdown trying to get to work. Do you know of any design flaws with the L98 engines?