I have an old but nice Robar W. German Sig P226 that has a cracked rear right frame rail. This was caused by the slide breach block pin being broken (fixed). The accuracy is shit but it cycles reliably (for now). I've stripped down the frame and mothballed it years ago and now found it. I saw a beat up Sig P226 in 40 S&W (no rail, short extractor) for sale. It looks like shit except but the frame looks decent. Can I simply put the 9mm slide on top of the 40 frame and feed it with the 9mm mags?