88 2.3L Cam Bearings Nightmare

[Winger]

I replaced this engine about 2 years ago cheaped out bought a rebuilt long block from one of those shop with the realy good deal! Put 5K on it and got bored put a cam in it and headers left the EGR tube off and plugged the port off for the intake yadda yadda. Well got about another 5K on it when the back two cam bearings spun and seized up and broke the camshaft! It had been squeeling but sounded like a serpentine belt pulley to me and of course I had no real Oil pressure gauge on the thing! So I pulled the head off took it to a machine shop wanted a little more performance out of it had oversized valves the whole thing done on it and bought a short block from racerwalsh. Should have bought the Head TOO! I put the rebuilt head on the thing get it running about two hours or so and notice that the rocker arms are loose and the Oil pressure is dropping down from 50psi at start up down to 25psi there towards the end at idle. I finally pull the valve cover off as the guys @ walsh say that it is not uncommon to have to drop dimes in the lifter buckets in the heads to get rid of the rattle on a hydraulic cam. Each dime is around .055". Get it off and I see the back two bearings are making metal again! So I'm pretty disgusted tear this thing down again and take the head back to the machine shop and this guy is dumb founded about the whole thing. I'm figuring he let one of his flunky's do some of the work and they didn't clean out the oil passages of whatever caused this in the first place. He claims no way that they did everything right but he'll go through it again. I come back a week later he claims he's found some new improved cam bearing for these heads and installes restrictors in the top of each bearing tower to help keep the pressure there at the bearing. He seems pretty comfident about the whole thing and I go put it all back together get it running sounds good drive it around a bit take it for emissions and the oil pressure starts dropping while I'm in line! Get it home pull it apart and now the middle two bearings are making metal like mad! HAS ANYONE SEEN THIS BEFORE???? I've already taken the head back to this guy but something isn't right! HELP!