Replacement Rods - Upgrade?

I've got my SB 415 torn down as the # 3 rod journal was bad. Crank is now ground and back in the block and I'm thinking I should replace the connecting rods with new ones as they appear to have already been out another time for a crankshaft replacement as, according to the original build sheet, the crank was supposed to be a Mopar Performance 4'' cast unit. Previous owner must have replaced with an Eagle 4'' 4340 for some reason. I assume the same issue as I'm having now and I'm thinking maybe a rod is bad causing the issue? I only have tools to check bore roundness which is fine, but they could be bent?

Rods in it now are Eagle "I" Beams which I read are 605 grams. The simple solution is to replace in kind with same rods but what about the Scat "I" Beams that are 595 grams in weight? Rebalance required you think? If so I'll stick with what is in it now, just though the Scat rods may be a bit of an upgrade.

I don't have the build sheet in front of me at the moment but the BOB weight was around 1730 or 1780 I believe.

Thanks for any suggestions you have.

Paul.