I had a pretty complete SP purple splash kit that I sold because it was too pretty to use. Even had an uncut frame. It was a gorgeous set.
Contact Tuna or BigEvil about your mag. Do not worry about the time it takes, as you would rather make sure its 100% working than to cheap out on a few
You shouldn't need any shims. look at the quote two posts up. That tells you exactly what to do. Brass things are called carriers.