So after three years of sitting in the son-in-law's garage, the 87 is back on the road. New clutch, flywheel, etc took care of most of the chattering. Took  it down to the beach this week to do some sand crawlying and danged if it didn't start getting hot. moved all the way up into the top of the gauge. I finally got back to the RV, cooled it down, added more fluid-over flow was empty and when radiator cap removed was no fluid present. put in new hoses when the engine was apart. anything to really look for besides head gasket? I find no other leaks. Oil is still clean and brown.

Replace the cap on the radiator as well.  It is the cheapest and usually the last thing replaced that can cause that issue.

well if you put fluid back i the over flow when hot and it did not suck it back in... thats a problem.  If you ruled out exterior leaks and the cap, it is likely that the fluid has made it to the cylinders. probably a head gasket.

For exterior leaks dont forget the small hoses under and behind the intake manifold.  those usually get forgotten until it is too late.

I would do a hydrocarbon test to the radiator while running.  that should tell you it compression is getting into the cooling system.

Did you happen to sniff the exhaust to see if it smelled sweet?

soon s I can get to town-way off down the beach right now-I will work on a new radiator cap and maybe a compression test. What I DID do was find out the the fan belt was way loose, must not have been set up right when the engine was being worked on for the new clutch. That has made a major difference. Still moves toward the top of the middle register, but did not climb in to the top one. After a 15 mile drive at 50mph and then 10 miles at 15 mph coming down the beach in 4 wheels LO. Now if I can just figure out what is the problem running slow. very rough engine performance. May be yet another vacuum hose off.