I read an article about a motoring journalist called Russel Bulgin who had a Mk1 midas, he was 6'4". In it he did 94 miles in 106 minutes, or was it the other way around? I wouldn't be surprised if Hans did not have a copy of this. Anyway, the point being, his car was a "dropped floor" version to cater for the taller pilot which was available to order. You're only a shorty, I'm 6'3" and managed for years in a Midas with a "flat" floor using a very low seat, ie no subframe and very thin cushion, have you really tried all alternatives? It would be a shame to sell and then realise a solution later.
I have a shell with a "dropped floor" and could give you dimensions if required. In essence, it appears that three cuts are made on the floor, one on either side of the seat, and one to join them behind the seat. The back end of the cut floor is bent downwards by about 2 1/2" to 3" and the gap around is filled with grp. This results in the back end of the seat being lowered by the same amount.
I fairly certain that Bob Ridgard made a very low seat, specifically for the Midas. Contact nos. at
www.ridgardseats.co.ukWhile travelling through Dumfries about 5 years ago, a white Midas passed us in good style. A loaded up Skoda could not keep up!
Hope this is of use.
Regards, Ron