It seems like to many pieces are wrong, the exhaust is much to close to the chassis.
Get in touch with exhaust maker and ask their advice, show them the photos.
Hopefully, they have cocked up and will be able to see where
I brought mine from a guy near Aylesbury, a few years ago. I thought it was a home made job.
I need to replace some of the side boards.
The frame and floor are metal, I like it because I can fit 4x8 sheets in it.
Non of the brake mechanism works now, but it does a job.
Getting shot of a load of crap timber on the local bonfire.
Saved many £££ not taking it to the local dump as they charge plenty, for anything non household or garden.