Noisy valve train in 235

[vintagetin]

I just bought an old '62 C-10 stepside for $700. It's been sitting for some 10-15 years. I removed the spark plugs and squirted some oil in the cylinders hooked a battery up and spun it over a few times. Then I did it again the following day and so on. After filing the points down, replacing the coil, and hooking up a balast resistor (someone had removed it) I started it up. It runs great! I flushed the oil and put some 20w-50 in it. After replacing the master and slave cylinder I drove it around the block a few times and the top end has still not shut up. At first I thought it was just hydrolic lifters just not holding pressure, but I've run it quite a bit and it's still making noise. The engine has good oil pressure. It's not very loud, but it's definatly making some noise. I hope I didn't wipe any cam lobs by not pre-oiling the old engine. It runs great under throttle so I doubt that.
Here are my questions:
Could the valves just be out of adjustment?
If so, to what tolerance do I adjust them?
I read that some models still used solid lifters, is this true?
Is light valve noise normal?