Hi MDS, You will almost certainly need the MX-5 seat rails/runners. Myself and a number of others have successfully fitted Toyota MR2 seats to the TR7, so as its a "proven" installation might be worth considering these if you haven't bought the seats yet. Not sure if MX-5 seats have been fitted but they seem very similar to MR2, so probably will fit fine. But as the others have indicated, the 7 seats are almost on the floor, so whatever seat you go for just check seat cushion height.