[400TT]

How hard is it to recess the floor, that's the way we went in our old DRB.

We didn't recess the entire floor, just enough to clear the seat sliders etc.

So you would be cutting out the centre area where the seat sliders and pan is. So effectively the edges of the seat would be a few mm above the floor(allowing for carpet of course). You would then effectively be welding in a dropped box like pan into the floor.

The more you take out of the seat, the less comfortable they get.

Plus it sounds like you are sitting quite high, lowering the seat gets you lower on the screen and more leg room under the dash. The more leg room under the dash also gives you the ability to fit longer drivers in. We sat higher in the DRB, but had more length to the pedals. With the Harrison we sat lower but had less length to the pedals, but it worked out you could get the same amount of comfort in both cars for longer drivers. Plus the more clearance under the dash gives you more freedom to move/bend legs on long trips.

From memory on our MX5 seats we just cut/bent the mount tabs so they were flat, then affixed flat steel straps between them to adapt to the Harrison seat mount cross braces.