[swissarmychainsaw]

Wow, I just realized that I asked this same question in a PM, here is the answer in case anyone else is adding seats like this:

Hey Nick,
Thanks for complements. Yes, I used Honda middle seats for both the front and rear seat. Yes I built the seat frames. On the back seat I used some of the parts off original bench seat. Front was just a a square frame and tabs bent to use factory holes.

I hope that helps!