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I think this is good news. As I understand it, a bent crank should only lock up when you crank down on more than one bearing cap, everything else being alright. That says that you have bearing shells that are not compatible with how the crank is ground for those two bearings. Either the crank is not what you think it is, or the bearing shells, or both, which may be an easy fix. I had a vendor send me the wrong bearings before, they were easy to identify because it was obvious, but probably simpler to do when the issue is simply the difference between 0.001, 0.010, 0.020, etc.

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Hopefully tomorrow I am going to be sending the crank and block back to the machine shop so they can re check everything and this time have the block to test fit.
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is this "magic clearance" just anywhere within the vertical oil clearance spec or are you referring to a specific sweet spot within that range?
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yeah I really like how these older cars are so unique compared to the newer ones; they sure don't make em like they used to!

I think this is good news. As I understand it, a bent crank should only lock up when you crank down on more than one bearing cap, everything else being alright. That says that you have bearing shells that are not compatible with how the crank is ground for those two bearings. Either the crank is not what you think it is, or the bearing shells, or both, which may be an easy fix. I had a vendor send me the wrong bearings before, they were easy to identify because it was obvious, but probably simpler to do when the issue is simply the difference between 0.001, 0.010, 0.020, etc.[/quote]
Well this seems like the most likely situation and also the easiest to fix. I am currently away from the engine right now but when I get back home I am definitely going to get a some calipers out and measure

For a good precise measurement I'd recommend a micrometer rather than a caliper.

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I have a micrometer but I am worried about using it on the crankshaft because I don't want to scratch the journals at all. and I also don't have any micrometer that can measure the id of the bearings. what is the tool called that should be used to measure the bearings? I would imagine you would torque down the caps with bearings inside but no crank. Is this the right way to do it?

Properly used, a micrometer will not scratch or damage the crankshaft journals, that's exactly the type of work it was designed for. For the ID you can either use an inside micrometer, or a bore gauge and transfer it's dimension to an outside micrometer. Inside micrometer is easier and more direct.

Have you confirmed that the crankshaft is not bent?

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Alright thank you for the help
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I just sent the crank and block to a machine shop to check for straightness

in answer;
{You should read up on engine building and not take my word for things.}
all the journals have to be on center axially and the OD's matching within tolerance for size and roundness. Otherwise, unwanted vibration will occur. A turning shaft has a natural vibration frequency and it has to be out of phase or it'll destruct due to harmonics. eg: if crank wasn't chucked properly, one end could be off more and machined out of round. (Assuming the crank wasn't already damaged, as noted. But they should have checked that before proceeding!) 10 thou is not alot of cutting, so more critical to get it right. Straight 8 cranks are longer so need more care in setup end to end and turning. Bearings are/should be 10 thou over(smaller hole size) now, if the crank was cut down 10 thou. If not, it'll not have proper clearance for oiling, too much friction(tight), or too loose and cause wear issues with movement. The bearings are also taking/dampening the load from the piston action.
General rule(heuristic) is one thousandth clearance for every inch of diameter. But it's usually specified for a particular engine service. eg, if racing engine different parameters based on WOT rpm range. Varies with the bearing material, oil type/pressure, lube method, etc. After the caps are torqued, the gap is measured to ensure clearance. End play etc. also checked.
They can "align hone" a block with caps torqued to make sure that the "holes" are all in alignment also so the bearings line up.

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The machine shop has determined that the mains are slightly out of round and will need to be align honed. The only problem is they need to remove the head studs to put it in the machine and are going to be charging 140 an hour for labor.
So, my question for you is this, has anyone had any experience removing head studs & how long should it take? The block has been hot tanked and cleaned recently so at least the tops of the studs are not rusty but I’m not sure if that means the bottoms should be relatively easy for them to pull out. Any help helps.

I believe-off the top of my head- that there are 36 studs