After the 5 year life span of the FIA seats, they can be inspected and used for another 2 years if they're still good. That means no cracks, the mounting bosses are still strong, belt loops are intact, etc.
I wouldn't buy a fiberglass seat. Get one of the newer composites. I feel that the COBRA seats are the smartest buy.

Thanks for the advice. I can have a friend weld a bigger plate onto the brace. Strangely, The FX-1 has a single allen bolt through the center of the back. I haven't seen a brace that fits it, nor does anyone at Corbeau know anything about it. But, since it doesn't need to be bolted to the brace I'm not going to worry about it.

hmm Here is my seat back brace. I got a good deal on the Corbeau seats. Just using them for practice on the track really. it was easier on my wallet to get started. I am sure I can turn around and sell to some kid want to be racer later.

But they have got me on the track. Think my seat back brace is overkill but it is solid.

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