I picked up a very tired IR 301 (not B) die grinder for $5 a while back and have decided to disassemble and clean it up. Other than the exploded diagram for the 301B, I don't have much to go on for how to proceed. I'm assuming that I should unscrew the large nut that couples the head to the body and go from there. Any other direction for once I get inside, including things to watch during reassembly would be appreciated. Like I said, I only paid a few bucks for it, so no big deal if I botch this.