Buying new heads few questions.

you need to remove the pistons to cut valve reliefs.

There is now a tool that can cut reliefs with the pistons still in the car, but I haven't heard any feedback yet. Most people opt to remove the pistons or replace them.

You are putting on an induction system that is good to about 7000 rpm. Are you sure you want to run old cast pistons and stock rod bolts through all this performance stuff you are bolting on? Do you really need Victor Jr's to achieve your goals? Bolting on high rpm speed parts to an aging short block is poorly thought out and a recipe for a spectacular failure. While your budget may not allow for a complete, well thought out rebuild, I would recomend waiting until you can afford to do it right instead of piecemeal.

In regards to your push rods, I believe the Victor heads use adjustable rockers with guide plates. You need good aftermarket high strength push rods that are engineered for guide plates. You factory ones are not. Do not re-use them.

Hard to say. See if you can find reciepts and see what they put in there.

If you don't know for sure, your gonna hafta do it yourself.