piston rings

new piston rings are going to be installed here soon as well as some other bottom end things, what break in oil would you guys use for this?

Alright, guys, I need your collective ford knowledge for the little predicament I'm in. I'm on my second 2.9 rebuild and I'm slowly learning from my mistakes from the first time I tried this. I recently purchased an 89 block from a pick and pull yard, the engine has roughly 140k on it, in decent...