Call Bob George and go through him you won't be disappointed. My 605 has a Indy rotating kit and Indy 426SR1 heads. The rotating kit came with a Callies crank with 2.2 rod journels, by all means use the 2.2 size rod journels. 7.1 rods and Diamond pistons. The block will need much less clearancing with the 2.2 rods.Dave