How about this 360 LA combo?

Do a search here and on bigblockdart.com for subframe connectors. If the car was an auto from the factory, it had a 904. A 727 will basically bolt in, although there may be minor floor tweaking involved. Nothing outwardly visible.

As for quench, there are a few variables such as RPM, rod material and clearance. Generally you want no less than .030 and the effect goes away beyond .050 or so. A standard Fel-Pro composition head gasket has a compressed thickness of about .043, so most builders zero deck and call it good. Now, if you were to run reverse deflector pistons and open iron heads, some simple math might be needed. 10.5 compression with tight quench, and completely deburred aluminum heads should be fine on pump premium.