I purchased a 4 scale system on Ebay. It comes with 4 postal scales and a flat board with 4 adjustable feet and a bullseye bubble in the middle to balance the board.
I setup my car yesterday afternoon and raced last night. The car was unbeleivable. I won every qualifier and the main for the first time in many tries.
I also found a good site to describe the balance process http://www.ground-control.com/?D=e04...ffa901ba6b5aaa
As Speedie has pointed out balancing the car is very difficult. I have not tried the lead weights yet. I just adjust the spring collars.
My car came out LF= 23.7%; RF=25%; LR=24.9%; RR=26.3%. This comes out to Lft/Rt=48.6%; Rear/Front=51.3%; and cross balance of 49.9% The total weight was 1430 grams. I was not able to get the weights exact, but it was close.
I also own the Integy System, which works very well. 4 scales are just a little faster, and possibly more accurate. Both systems worked much better than my previous tweak board.