'69 Valiant 4-door w/bench seats - cramped at 5' 10"?

I have seen seat relocating plates -- maybe at Summit Racing. These are flat metal plates with two holes, or one hole and one stud, that you use to offset the seat track back (using two on each track). I just made a set for my 67 Barracuda with a 3-1/2 inch offset (I'm 6'1"). My design is a single long flat bar for each track -- I thought this would be better for keeping the track square and avoiding jams. Unfortunately I haven't had a chance to install them yet.