Checker. Go to partsamerica.com, checkers website. You can either print out the page with the price and they'll match it, or pay for it online and choose pickup in store. I always try for the 2nd option, they pull it, and it's sitting there with your name on it, waiting for you. My store usually calls within 15 minutes of me making the order to let me know it's ready for pickup.
Listing was for a 95 k3500 6.5 diesel. As for how it works, it's BITCHIN. turns the motor over like it's a little honda 4 banger. Truck starts off one battery showing 11v without issues. 5 count on the glow plug switch, then starts in under 1 second.
Still need to know that bolt size. I tried threading in a 5/16, but it only went in one thread before feeling too tight to be right. Could be dirty threads, could actually be metric threaded. Might be 5/16 fine... anyone know?