Too Tight Rebuild

Maybe someone else can answer this cause I'm not sure but the problem may be the ARP main bolts. I know when you install ARP studs you have to have the block align honed because their diameter is larger and moves the main caps around a little. Not sure if ARP bolts cause the same issue but the guys are right that you need to narrow it down by starting with just the crank installed. If you can't spin it easily with your pinky finger there's a problem. If the crank spins free the next step is to check the ring end gaps and if ok install a piston and check the rod bearing clearance.

And why are you using ARP bolts yet torqueing them to stock bolt specifications? They always come with a spec sheet telling you what to torque them to and that's exactly what you need to do. They are a better bolt that'll give the main caps more clamping force when torqued properly. When not properly torqued they aren't much better, if any, than stock bolts.