Thanks for your reply.
The previous owner of the car had this seat mounted (on both sides), so it should fit. He was much taller than I, and he had the seat attached, via some hand-bent steel traps to some similarly fabricated rails. I'd like to move the seat much further forward while also mounting it with better-made parts. I'd also like to use sliders on the drivers side, as I mentioned.
Sadly, the car is at a shop right now, having some work done that I couldn't manage myself. I should get it back in a week or two. I'll test fit then, and I may contact you about your custom rails then.
2009, STR & DD. 1995, HPDE. 2004 MSM, sold. 2010 Mazda3, hers.