Ray,
I bought a R.M.T. frame a few years ago at a gun show. Dementionally it was fine. Unfortunately while shooting some heavy loads the bottom corner of the grip flew off. The part around the the mainspring housing pin.
I alumi-welded it back up, and hand filed it into shape. Bought a .22 top end and now have a very light almost all alloy .22 1911.
Hope you have better luck...
Joe