Thanks for the helpful advice, and get stuffed mohick. Thanks Sawmikaze, the Stihl dealer sold me an 021 spur sprocket which he says I need. The rim setup looks good, dealer didn't mention that, maybe he was trying to keep cost down? Was $49 for the spur sprocket here in NZ, lol...
If you are buying from a Stihl NZ dealer, there's usually a 'because we can so **** and kiss our arse' tax built into the pricing. If not from the dealer then Stihl NZ HQ.