Chesterfield and Stocksbridge...
You'll need pink and yellow rears, and lilac and 2x pink fronts - all Jaco. At Chesterfield you'll start on pink rears and lilac fronts, and when the grip gets to the point where the pinks start to slide, switch to yellow. At Stocksbridge you'll start on pink rears and yellow fronts, and when the grip comes up you can try a switch to 2x pink fronts. These are for a BMI or 12R5.1, YMMV.
Parts - you have the list above, both good shops to deal with. Bodies, the Protoform AMR is the safest, the Parma EE1 has a bit more steering, and the Black Art Bomb'r gives the most steering.
Schoolboy errors - not building the car properly! Front suspension must be free, polish kingpins and shim so the spring is not compressed (when car is off the table) but there is no free play. Rear pivots must be free with no backlash. ALWAYS start with kit settings unless you have clear evidence that isn't the place to start. NEVER change more than one setting at a time when testing, unless you know exactly what the car is going to do if you change two or more things at a time.
9650 is the best servo out there for 12th IMHO. For kit choice, go to your local clubs and see who's running what. Try to buy the same as them so you can benefit from set-up advice. If in doubt, buy an Associated 12R5.1 or BMI DB12RR second-hand. Both will go very well out of the box.
HTH, please come back if you have any more questions.
