I've been tinkering with this on and off and today I was finally able to finish up under the hood. I used an old forward only esc to drive the fan motor but it is causing problems with my main drive esc. It works as normal with the under hood stuff turned off but after a short period of time if you have it on then the trucks esc goes into protection and won't come back on until you switch it all off and then back on. The under hood esc, steering and dump all work fine no matter what. I did have some problems initially with the little motor under the hood effecting the servos but I wrapped their leads through one of those ferrite rings and now it's fine. I'm guessing this motor is causing the issue but I don't know how to fix it. I'm not sure why it doesn't effect the esc right away and the amount of time it takes to screw up changes with each run. Maybe you electronic guru's out there can give some feedback?
I should mention that the forward only esc is a Novak Arrow and the other is a Proboat...
http://youtu.be/E6S_KtdWziQ