Another 'what is it' kart request for identification

Mini Bike & Go-Kart Parts

Hopefully someone can identify this cart 'frame'. I'm thinking it may have been made for a kart rental track since it is so heavy. Overall it's almost six feet long.
Also under some of the paint I see several 'safety' stickers. Several holes has me thinking it may have had a body on it at some point. There was also a 1/8" thick floor pan.
Thanks, John IMG_4117.JPG
Looks ''very'' stout whatever it is ….
Cool also that it has the cassette mountings for a live axel.
Also looks like you can put a pretty ''hefty'' engine on it.:p;)