Hi Justin33 - welcome to the board... great first post with your Kinwald DoubleX .... a fantastic buggy & a car that can still show a modern racer a clean pair of heels!
Those dished wheels are from the later XXX car - you'll notice that they are slightly wider than the five spoke wheels you have... as for tyres, it all depends on what surface you a going to run it on.... if you are going to race the car (which i'd recommend you do) see what the guys are running at your nearest club!
Parts for these cars are actually becoming more & more difficult to come by... I decided that I better stock up on a few essential parts now that I am racing my XX... I managed to score a front bulkhead from a Hong Kong supplier for the RRP but they are now out of stock - & it seems that this is now a discontinued part

I also got a pair of front wishbones from ebay but I had to pay a premium for them. There are some bulkheads for sale on ebay.us but they are extortionately priced!
Some parts it seems are easier to find & of course many parts are shared/transferable with its younger brother the XXX - namely diff, gears, Slipper assembly, shocks/springs, wheels, bearings & driveshafts
