I have been looking around the internet at pictures and it seems to share some details with karts from Rupp Industries. Maybe not a racing kart, but possibly a "fun" kart with knerf bars. I haven't been able to nail down a year, but more likely a very early model. The big thing throwing me off is the bar that wraps around the base of the seat.
Any of you familiar with Rupp Karts see a resemblance? I would be interested to learn what the original engine might have been.
Brent