Custom seat brackets/sliders?
 

Does anyone know who can custom fabricate one to work with the oem seats? I like the oem seats but I want to feel more immersed in the car rather than feel like sitting on top of it like a horse.

The issue is not with the brackets, remove the seat and see for yourself. If you want to lower the seating position of the OEM seat you will need to remove some foam, reconfigure the springs.

If you have done this, I would like to see a DIY on the method. I would like to lower my seat so that I can wear a helmet but do not want to loose the creature comforts of the electric seat adjustments.

I didn't want to cut up the seat, I added extra headroom by getting a Kirkey seat on a Wedge seat bracket. I do believe someone here has modified a stock seat to add headroom.