The engine is the same- in the early models 900's anyways. The difference is in the hyd or manual dump bed , front bumper or not, and whether it has the hook up for hyd tools. Back then in the early years, it was the WS ,-( worksite) with bumper and hyd dump , GP General purpose - no bumper and manual dump-( I think), turf with extra features. ? and the recreational-( usually camo) I am sure members will chime in with more exact information. You can tell the year model by a certain number of the serial. I can't remember if it is the 7th or not.
I had a 2005 WS and now a 2011 WS no cabs though.
Like Dennis was saying, we have some good folks on here. Messicks Eqpt has parts diagrams to download from their website and wonderful parts people on the phone to help you get the right part and they can find the year machine you have- just give them the numbers on the plate there across from the the battery. You will sure like the diagrams they email to you instantly. Just choose the category. bordercollie
edit, we also need to figure out why it ran hot so it won't happen again. If he didn't do maintance , it coulda been just a clogged radiator.