If you follow the DIY here on the forum, you should be perfectly fine. The M1 has been reported to lose you low end on nearly stock engines, but I believe the "modded keggar" does not.

I managed to pick one up off a friend the other day. He did all the work for me, only cost me about $150 for the whole thing. If I had the tools, the time, and the space, I would have done it myself, but I didn't, so I spent a little cash. Now I just gotta find the time to get it installed.

Ordered the Hughes aluminum plenum plate, should be here on Friday, my day off. We shall see what happens.