This guy seems to just be looking for reliably built and possiblly cool looking seat. I don't think a fixed seat with head restraint is really what hes looking for.
I think maybe something like a sparco r600 would be more up his alley unless he has some serious aspirations he didn't mention.
Antihero
Putting AMS garbage, and $500 ebay wheels on a Z is like dressing a Victorias Secret model in a Walmart dress and Payless shoes. You're embarrassing yourself.