Combiness, if the fins are really messed up, a radiator comb won't work, anyway. A radiator comb is designed to 'dress up' fins that aren't all that bad. When the fins are crashed, smashed and laid over flat, only the old-fashioned way will do it! Maybe after hours of work with a pick, a radiator comb will help to speed up the process...but like the Guru said, the freakin' spacing does not match !!! Arrrrrrrgggg..another one of John Deere's crowning achievements!
(I was just looking at one of my radiator combs..it has six sides to it..they are indexed at: 8, 9, 10, 12, 14, & 15)
Maybe Deere mis-matched the spacing pertaining to a 'common tool' so they could sell a "John Deere Cooling Fin Alignment Tool". No telling what the price would be..I would venture to guess that it would be in the high-$ 30's $.