You do not have to modify the seat!
I mounted the front of the seat to a 1" piece of square tubing going across the front of the seat. The square tubing will have an offset to the outside of the car by about 1.5" (meaning it will stick out to the outside of the seat by 1.5"). The rear of the seat attached to the seat tracks directly. Take the seat tracks and mount them parallel to the trans tunnel; kinda like this \\ //. Then mount the 1" square tubing to the front of the seat track once the seat is positioned straight ahead.
Sounds more complicated than it is, just make sure your tracks are perfectly parallel with each other, a slight "massaging" of the trans tunnel can help for the front inside edge of the seat.
This way gives you adjustable distance to the pedals, a slight rake to the seat, and the seat will travel parallel to the trans tunnel while always staying straight ahead.
I used Miata seat tracks thinking that they would fit better but, the performers are very comfy!