In the original post , he states that he removed the heads and the crank would still not turn. I think that eliminates any valve problems.  I believe either crank or cam is making contact with rods or block when moving front or back with thrust clearance , I would rotate crank while prying crank or cam back and forth against thrust  and see if locking and unlocking occurs. since rod contact was already a previous problem , I would suspect that.

What size range adjustable pushrod do I need for my 390 block, TFS heads ,Morel standard travel  roller lifters,10.16 deck height ,1020 gasket, POP rockers ?   

Thanks for all the comments , I feel much better about running it as is. I'm not a engine builder or a machinist but have been a truck mechanic for the past 40 yrs. and thought it would be interesting to assemble this engine myself, thinking it would be fairly straight forward but from the beginning its been anything but. Was planning to use my old block but it sonic tested too thin in spots and looking for a acceptable replacement took months and a few road trips. The only good block I could find was a D4TE with the extra main webbing that had already been machined. It looked great ,sonic tested good but had some pitting in one cylinder, thought I could just have a sleeve put in and didn't realize would have to bore and deck it again, 5 months at the machine shop , got it back and installing the camshaft, had to shave two cam bearings to .007 clearance  to get the cam to rotate freely. Then measuring the piston skirt clearance on one cylinder .002 larger than the rest . The main clearances all measured .0025 - .0032 so that was nice but now as I'm mocking up a piston and rod on cylinder no. 4 , it measures .007 in the hole and when I used the same piston and rod in no. 1 it was .005 in the hole.  Is this acceptable ? The machinist is a one man show been doing it for 50 yrs. very FE experienced and a really nice guy, he said he square decked it, maybe he's having vision problems.  Also, when I torque the main caps to even 70 ft. lbs. my camshaft becomes noticeably harder to rotate. Is this normal ? It makes sense to me that if the heads torqued down distorts the cylinder bores, that the mains torqued would distort the cam tunnel. I think I'll install new cam bearings and make a cam cutter out of an old camshaft as Brent suggested and see if that helps. Should fitting the camshaft be done with the mains torqued ?  I'm not looking for perfection , I realize this is a 50 yr. old truck block, just want to know what is acceptable. Even with all these issues, I am enjoying learning this process and feel very fortunate to have this forum with so many good people with so much engine knowledge and so willing to help.

Thanks Barry and Joe , one of Joe's previous posts is what got me concerned about coating and wanted to hear of other experiences ,  .002 seems like a lot to make up with coating. Would I be better off honing the other cylinders up to the larger one and then getting new pistons ? or am I getting too concerned about clearance ? RaceTec said the only problem with .005 skirt clearance would be noise on cold start up, which I might not even hear because its going in a desert race truck with no mufflers

I finally got my D4TE block back from the machine shop , took 5 months just to machine the block. I'm using AutoTec 4032  pistons 4.090 bore and there clearance spec. is .0028 - .0035
7 cylinders are  within ,but 1 cylinder is at .0055 measured at the top of the cylinder with the head torqued on and the bottom measures .0050  all the other cylinders have a similar .0005
larger bore at the top than bottom of cylinders.  My thought is to have 1 piston skirt coated.
I talked to Calico and they said a heavy CT3 coating which is a moly teflon base would add .002 to skirt diameter.  I've read some posts about coatings  being not as thick as promised or wearing off quickly, so my questions are :  Has anyone used this process  or any other process or coating company that you would recommend, and has the thickness held up over time. also is the .0005 larger bore at the top of the cylinders normal?  the engine is 4.250 stroke wont see over 5400 rpm and no power adders.

Starting to assembly my D4TE block, using durabond FP-33 bearings , I first put them in with the hole facing up noticed my mistake then removed them and put the same bearings back in with the hole facing down. the bearings went in and out smooth and straight and looked fine so I reused them , I measured clearance with a bore mic. at .003 - .0035 The cam went in easily from the front thru the first 3 journals , the 4th got a little tighter but still turned easily and the last journal had to give it  a little tap. I could rotate the cam with the bolt and the dowel by hand but it took some effort. I removed cam and installed from the rear as a test, same thing smooth thru the first 3  and binds up a little on the last one. I've searched old posts here and read that its fairly common to have cam journal misalignment and about shaving the bearings with a knife and scotchbrite and also using a hammer and a drift  on the cam next to the journal , I decided to use the 1st method. I rotated the cam for a while then removed and noticed wear marks on 3 different bearings ,I shaved a little off each one and cleaned them up with the scotchbrite then installed cam and  was better, I had to repeat this procedure one more time to get the cam to turn easily using the bolt and dowel, then checked clearance and there between .005-.007 .  So my questions are ,  is .007 clearance acceptable ?    and is it acceptable to reuse cam bearings that were previously installed then removed ?     This is a 447 with a .620 lift 231 @ 50  hyd. roller .  any advice will be appreciated

I plan on using the springs that come with the TFS heads for hyd. roller

Thanks Barry , yes theres water on the other side , the pitting extends 3" up the cyl. from the bottom, the water sat in the bores for some time the pistons had to be pounded out with a hammer the block has been decked and line honed all other cylinders are free of pitting I have not inspected this block in person yet, it is a 3 hour drive from me but i'm thinking of driving down with my trusty ebay sonic tester , good 390 blocks are becoming hard to find in so. cal.