Found some tall d e ck motors that were built an y pros or cons beside longer push rods intake manifold distributor e being higher ???

I have a old gm tall deck and they are fine, water pumps starters alternator brackets are the same, I run aluminum heads with retro fit roller lifters so had to measure the push rod lengths, they make tall deck intake manifolds( all single plane) a lot of the tall deck intakes are machined for standard bbc distributors, you can also get tall deck blower manifolds, I have had no fitment issues with mine. It’s an old tall deck truck block, 4 bolt mains and had no real problems doing stroker 496.

If you get an intake not machined for standard distributor they make slip collar ones that you can use, if you use the spacer plates to run a standard deck intake manifold you would definitely need a slip collar distributor.

Exhaust location? I thought it needs to be moved up and out ~1/2"

I got enuf wiggle room with my e x

I installed my engine the put exhaust in, so I had no issues, the blocks are I think .400 inch taller so it should only move up the exhaust a little, guess if your running twins and they are super close together it could cause an issue.