DRIFT_BUGGY, I have converted both a Kyosho SP2 777 and a Kanai III. Here is what I am using right now:
SP2 777
Diffs 3K/8K/2K
Kyosho Big Bores with Medium springs 50wt/45wt front/rear
Neu 1512/2D and MMM on 4s
14T/47T gearing
Mechanical disc brake front / motor brake on the rear
Wt. 7 lbs 9oz w/o batt
Kanai III (converted to CORR truck)
Diffs 5K/7K/2K
CEN TR shocks with stiff springs 50/50wt oil
TeknoNeu 15152.5D and MMM on 4s
14T/46T gearing
motor brake all around
7lbs 10oz w/o battery
I have the TCD diffs but never used them.
Here is a really old picture of both buggies.