Outer Limits 4x4 Board

Hi guys ive been trying to track down a rear canopy for my hilux, the flexiglass type and im finding it hard to get a hold of one thats actually the correct dimension! My trey seems to be a very odd size. There is a tub and canopy off a 1996 model for sale, just wondering if anybody knows if Toyota changed the mounting points of the trey between 1996 and 2002? Even older models, was there a specific year where different model treys stopped fitting ?

Cheers
Brad

Nothing a grinder welder and some piss won't be able to fix