ALLEN S, JOSH - I live outside Madison and have used two different shops in this area. Was not satisfied and used one in Fond Du Lac recommended by Dave Kirk for machining on my K321. There's a K241 waiting for $$$$ to be rebuilt in the shop and it's going back to FDL.
A KT17 will not be cheap to totally rebuild. My Buddy rebuilt his in his off-topic tractor about 10-15 yrs ago. Bored both cylinders, ground valves, ground crankshaft, all new seals/gaskets, rods, pistons, rings, wrist pins. I saw the bill and it was over $1000.
SO, that makes Matt's suggestion of a new Magnum 18 that much wiser. Several shops I talked to always said the series 1 KT17's never lasted over 1000 hours. The M18 is a much better engine.