There are a few out there. The only ones I have seen, less than 5, have all been 318's. Just weld the roof shut. Worked for me.
Thanks for the suggestion - That's a possibility. There are good write-ups on other forums for removing all the motor, tracks, frames, etc., splitting the sunroof open, then welding just the exterior sheetmetal skin in place and filling the gap prior to paint. Then you have to deal with the headliner. Removes roughly 40 pounds from the top of the car, which is huge, and of course does not leak. A nasty job if you want to go for maximum weight reduction.
I don't weld, and need a clean shell anyway, so I thought it would be a lot easier to start with a slicktop and avoid all that.
By 318's, do you mean only the 1991 models, or did some of the older M10 cars come in slicktop?