Good Luck with finding a group of folks that own semi auto Madsens. Lots of folks have made their own semi from a parts kit. As far as builders go Dennis (MMC) has done a lot of them. Sorry if yours is not running well. Another builder was Gordie, I believe his design was out before Dennis started doing them. Myself in all of my dealings with Dennis they have been good. Heard of a lot of builders that started other folks builds and returned parts and lots of interesting stories. Good luck on your stock hunt.

Later 42rocker