The plastic diffs work great ,but the org alu ones are the best there is...im running it in the rear (will get one for front) app 20packs or more, and still almost NIB feeling..
7800 is a good one, i used to run it, around 12-13T piniong is a good starter
You will not break any arms on it.
Shock mod
Reinforced arms..
A lot of CA thin one...let it dry then you are ready...i finished it with 2comp epoxy, no need for it