Well, went under the van and ran it to find the leak and it appears to be
the BIG hose coming out of the plastic distribution block ahead of the right
bank of cylinders, it popped a wee little hole in its side. Now, what to do,
just replace that one or all of them that are looking kind of borderline.
I've only replaced two other hoses on the van since owning it (not first
owner), the one coming out from water pump to rail hose(elbow shaped), and
the little short one form the thermostat housing to the back of the van(big
to small). The van is a 90 and I have no idea if hoses were replaced before
I got it.

Also another thing, when I was under the van the left side bank valve train
seemed to making more noise than the right, not overly harsh, but definitely
off in some way. I do have the 1.25 ratio rockers with the swivel feet
installed, but I don't remember them being quite as loud before, hmmm, maybe
it needs adjustment?! How quiet is the valvetrain supposed to be? Anyone
tape record there engine ever? Maybe that's what caused the overheat, valve
adjusters gone loose? I will have a peak in there too I guess, man, gotta
remove all that engine tin in the way.