Most of the pre-assembly checking and measuring is complete. Checking to make sure parts are in tolerance for the most part is done on all rebuilds while in my view, setting clearances to a specification is part of "blueprinting".
Anyway, I swapped out main bearings to achieve a clearance of .0028-.0033 which is more variance than I would have liked. The crank is +/- .0001 on the mains and there was even less variance in the bearing which means the main bores in the block were not machined as accurately as I would have liked but are well within tolerance. I am not thrilled with this but I will move forward with it as the fix is more hassle than what it is worth. Initially I had maybe .001-2" of crank thrust clearance and it was spongy feeling. I had to do a ton of work to thin down the thrust bearing to achieve a .0055 thurst that was solid. I then moved on to the rods where again, I had to swap out three sets of rod bearings to get them all at a perfect .0025-.0027. The pistons were next and after measuring them, piston to bore clearance is .0028 - .0032. That is at the bottom of Autotech's specification for their 4032 piston but again within tolerance. The pistons were +/- .0001 so again the variance is in the block machining. I would like to see .0030-.0032 but as I am within tolerance, I am not sending the block back. The #1 rod and piston were installed in the block and I measured a perfect .000 deck clearance.
I reused my old timing -10 timing chain which had some stretch in it and was very loose on the 455 but barely slid on this motor. I set the crank gear on the 0 slot and lined up the dots. When I put on the degree wheel, this ended up at 107.5 degrees BTDC. It was 108 with the same cam and timing chain on the 455 and the difference is within my ability to measure it so I will move forward with that.
The freshly milled heads were installed with an old gasket to measure piston to valve clearance which came in at a sufficient .1615 on the exhaust and .1575 on the intake. My old push rods produced an acceptable pattern on the valve tip and are the correct length.
I had two problems that were keeping me from doing the final assembly. First, I had some rocker arm misalignment that I missed the first time around. I used a set of AFR adjustable guide plates for a small block Chevrolet application on five of the rocker stud pairs and that got the all of the rockers aligned over the valves. Second, I was coming up with .0085" camshaft end clearance. I am told spec is .003-.007. Turns out in my hurry I swapped the wrong dial indicator on my base so instead of .0085, the correct reading should have been .00425 which is right on spec.