Mike - if you need a GOOD shop to mag and pressure test the head, I highly recommend Gary Camp. He took over Ed Hale's shop after working for Ed and Pat for the past 25-odd years. The sign over the quansit reads GMC AUTO MACHINE I think, but still looks the same inside the shop, same location on Wintergardens in Lakeside.
I can certainly feel your pain, having been snakebit on a 3/4 race 235 with low miles. PO's shop left out the baffle in the crankcase for the road draft tube for starters. Then a Crower valve spring broke, dropping a intake valve. Mag reveled a crack above the water jacket on the FULLY PORTED HEAD.:( #6 was also 20-lbs. down on compression, so tore it down for the baffle, rings and rod bearings. NEVER had great oil pressure, but it got sick 1-1/2 years later on I-5 in San Clemente. It had spun #5 rod bearing, but never knocked - just ran hotter, oil pressure dropped to around 12 lbs. I call this mill THE JINX !!! I have a couple freebie motors, so I just might build it again with a used crank and bearings!:)
Tear the 250 down and RECHECK EVERYTHING!!! Gary can help with your build.
Good Luck, Tim
