Really spend the time with some GT3 seats to see if you like them. I think the seat back angle is perfect as is the mid-section and shoulder support. In a G it should be a matter of just getting the intial shimming right. Pretty easy fab stuff.
Having said that, they really work best for <34" waist and somebody that is 5'10"-6'2". Also, the deep bolsters coupled with the failrly wide door sill in G will make getting in a bit of a butt freefall and getting out more difficult than stock.
I've had three sets in cars I used on the street and loved them but some do not in sreet car. On the track you can't live without them. The weight loss is a must have too.
