Here is a thread I posted a while back on another forum documenting a 3-point seat belt installation I did in case anyone is interested.

First off, let me say that I in no way claim to be an expert in this type of installation and in no way recommend that anyone do it this way or that my way is best. I purchased this kit from http://wescoperformance.stores.yahoo.net/nonresebe.html and anyone attempting this should follow only their instructions & recommendations and not mine.

Sorry...anyway, the belts I chose are the ones designed for a convertible/hardtop as I wanted to mount the shoulder harness pivot behind the front seat below the quarter windows.

The belts came through a much brighter red than I had wished, but since it's the only shade of red they offer in this style, I'm stuck with it. It shouldn't be too bad though.