Rebuild issues...
 

So i did rings and rod bearings when i put the new engine in my car...

Once i torque the rod bearings i can not physically turn the crank... 3 ft breaker bar on the crank bolt and it won't budge a MM. Back the rod nuts off and it turns... What's the deal here? The manual i have says 42ft/lbs torque on the rod nuts. But i can't budge the engine when it's torqued... All the bearings are in correctly and there are no over laps... Im at wit's end with this... Any input would be greatly appreciated!

Did you plastigage the bearings?

did you put the right rod caps on the right rods? each of the rod and rod caps have a stamping number on em.

+1 it doesn't sound like it. You'll want to do this first to see if the bearings are indeed too tight.

Did you have any work done to the crank?
It should turn real easy.
It sounds like there may be "tolerance stack" meaning that the crank is at it thickest acceptable point and so are the bearings making them too tight. I believe there are also bearings made to fit after the crank has been machined so they are purposely thicker. You didn't accidentally put those in did you?

^+1 That was my thought - oversize bearings. The crank should turn easily.

Well i gotta ask, you did use assembly lube right?

Caps were on backwards... :/ I have no idea how i pulled that off, as i marked each one independently to the rod...

Engine is still "tight" to turn over but it turns now... I think once it seats the rings it will be much better...

This is just my opinion how ever...

Don't try to run this engine until it turns easily ,if the bores are lubricated it still should turn easily,I believe you could/may have damaged bearing shells and this won't go away.
Turn the engine and remove the caps and check the bearing for any marks then you will know.

plastigauge the bearings or risk doing it all over again after you fire it up.