[400TT]

MX5 seats are one of the slimest(base height) I've seen with sliding rails. They also have a very slim back so you can get the seat back further. In our first Cobra(DRB) we recessed the seat rails into the floor to lower the seat further, but that was with a Cobra replica seat. The next Cobra with MX5 seat, didn't need the seat lowered, but needed to modify the rear wall to get the seat to slide back far enough for my tall brother.

My brother raced with a Harness using MX5 seat for a couple of years. The headrest section is narrow enough that harness still sits on your shoulders. It's not ideal though as the harness can sit a little wide on your shoulders if your shoulders are narrow.

The best sources for MX5 seats were Jap Importers & MX5 clubs.

To help with fitment, you will probably find that the passenger seat will fit the drivers side better and vice versa. That's due to tilt handle etc.

Tilt columns, a few guys are using the later columns e.g. BA Falcon etc. to get tilt. What factory column is your kit setup for, assuming it has all the mounts for one already.