Well... put some pretty serious effort into making the factory seat bases work as a pedestal for the new chairs. I tried to keep as much of the old seat base/slider as possible to keep a near-stock location. I knew they would raise the new seats higher than the factory units, but not this much. There is more base-to-fanny thickness in the new seats than I thought. They just sit too high to be practical. (no sense posting pics... failure is painful enough without evidence)
I don't mind looking through the upper half of the windshield, but my hair brushes the headliner, so there is no way a helmet would fit. So... it's back to the drawing board. It is rumored that Thomas Edison once quipped that he didn't fail 2000 times trying to make the light bulb, he just figured out 2000 ways NOT to make a light bulb. So I have figured out a way not to install aftermarket seats. I have an assortment of spacers and I found some locally available flat steel bar, so I'm going in a different direction. I'll sketch out some dimensions and see where I end up... Thinking cap, where are you???...