My wife has an cool barn find f100 with a 223 / 3 speed bolt action. 3rd gear is pretty growly. I wanted to pull the transmission out and go through it this winter. Does anybody have a good source to find a 3rd gear for this thing? 1st and 2nd are nice and quiet. I've googled it to death and have not really found a source. I'm not even sure what the Trans model number is. I can't find it anywhere on it. Thanks guys.