Hey guys just thought I would share my discovery, well maybe a discovery, I just bought a set Sparco Sprint V's and they fit perfect in my 77. No tunnel or hump bashing required. I was skeptical they were going to fit because Sparco's website says the width of this is seat 20.2 inches, but when I bought these I measured them first and the width of the seat at its base is only 16 inches so ignore what sparco's website says, these fit perfect and actually have some room to spare, i'll post pics tomorrow when there is enough light to see, I have two seats by the way neither have ever been mounted and I am selling one of them, it's in the classifieds