Not meaning to offend you but if I were you I would get some help locally.

Since it has roller rockers it likely has other expensive high performance parts in it. If there is rust in it, it likely has rust on the camshaft lobes, cylinder walls etc. If you run it with the rust\debris in it you risk ruining the whole motor.

If I were you I would take it to a reputable local engine builder and have them take a look. Spend a couple bucks now to save hundreds later.

If you want to learn how to do it yourself then research as much as you can and find someone that will kind of "oversee" what you're doing. Mistakes are expensive.

Trust me, when it comes to boating, it's no fun towing your boat to the lake just to look at it on the trailer while all the Chebby boys are out on the water with the chicks. Make sure you're race ready when you unload.

______________________________________
'69 Coupe, 351C
'05 Super Crew 5.4L
'06 Fusion SEL V6 (momma's car)