Guess I’m missing the boat, thought it was for a 3500 or less rpm Durango, could put some icon 742’s in it if you want and stay with pump gas. Not knowing what pistons you have I am just guessing. Putting a scat light rod and a light piston will save you for balancing but that cost money also, nothing wrong with external balancing on lower rpm motors like this.
But I don't have those. I was hoping to use up what I have here. Don't know the CR difference between what I have and the CR107. I guess I'll have to get the number and look up the specs on them..