I will be honest Barry and say that I was slightly disappointed last year at the lack of trade stands there wasn't a great deal of choice, with that in mind you might do quite well as you have a better range than most. G & M don't go as it clashes with Zwolle so you would be welcome if you do decide to come up.
If you are staying over then there are loads of B & B's in Penrith itself and the visitor centre is only 5 minutes out of the town and just off the M6.
All of the usual suspects are there diorama wise, The Lancashire lads, County999, JCB Bloke and quite a few others. It's actually a great family venue as there are lots of other things to do in the visitor centre with shops and restaurants so the non tractor fans have something else to do.