Welcome aboard Drew54. Probably would have been good to have run a compression test before teardown as it would have told you overall condition of the cylinders, but thats OK.
With the valves still in the head, turn the head upside down and as level as you can make it. Poor some water into each combustion chamber, enough to cover the valves then let it sit. If all valves are seating properly it shouldn't leak, if it leaks you'll need to pull and check the valves & seats.
Burnt valves on these old engines are quite common.
Clean the tops of the pistons as clean as you can get them then inspect. You're looking for holes, cracks, indentations etc.
Check the cylinders for scratches and holes or any other abrasions, if you can feel them w/your finger nail the cylinders will need to be mic'ed and probably bored out oversize.
Does the engine spin fairly easy? It should. If not you'll need to drop the oil pan.
Actually I recommend you drop the oil pan and give the internals a good inspection. Plastigauge the main and rod bearings as that will tell you if you need a rebuild or not.
If you plan on just checking it out then getting it running as is, make sure you put the lifters & pushrods back in the same locations they were in as they've broken in there.
Depending upon your skill level, the head isn't hard to disassemble and cleanup but if not you're looking at around $250-$300 for a complete head rebuild that would include new valves, new hardened exhaust seats, guides, the head magnafluxed for cracks, hot dipped and cleaned. I've had a couple done by a local machine shop and am very happy with them.
Cracked heads are fairly common from what I've read here. Look for cracks around the valve seats in the combustion chamber. Sometimes the only way to tell is by having the head magnafluxed by an automotive machine shop.
A good engine gasket set will run you around $100, I recommend using the "Best Gasket" gasket set. It's made in the USA and theres no better.
Do a lot of cleaning and inspection but be prepared to get the head checked as they generally need the most work.
Good luck
Dave
