What new parts would I need to do that, just the longer links? If that's the case, is the best place to get them from?
In an update to MP's mobility, the replacement brushes came from Honk Hong at last, I put it all back together and the motor is running just fine. It'll be interesting to see how long it lasts now before it dies. I've also ordered one of those generic motors from eBay (China) as a backup for when it does eventually bite the dust. It'd be great if they're actually good, as it means mud bogging can continue, as for 10 quid a motor, who cares!