Most ridge reamers are adjustable over a wide range of cylinder diameters. There's at least a hundred of them listed on Ebay right now, new and used. Lisle and Snap-On sold the same basic design, a lathe-type cutter that climbed a very fine thread and cut the ridge out from the bottom up. I used the same one for over 25 years, on untold dozens if not hundreds of engines, and never managed to wear it out. I think it followed somebody home while I wasn't looking one day!

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!