This adapter kit is designed with the Custom Bike Builder in mind. It allows to use a Twin Cam "A" engine, as used in 1999-2005 Dyna Glide and 1999-2006 FLH/FLT models, in conjunction with a 1985 thru 1999 Softail transmission, in most frames that are originally made for an Evolution Big Twin, such as our Wide Tail, Super Ass, or V.G. frames. There is very little grinding on the engine cases required to allow for wrench clearance. The adapter plate is precision machined from a solid block of billet aluminum for strength and true Custom Style. Kit comes complete with all necessary hardware as well as comprehensive fitting instructions.