Hi all I have quite a number of questions to put to you intellectuals

all involving an Emaxx.
I know there have been many custom maxxes built and they have inspired me to try and make my own so the basic outline I had in mind was:
FLM Chassis...
And thats it

This is where I need your help because I am on a tight budget so need to get this mostly right first time. I need help choosing diffs I don't mind spending money on quality as long as it works and lasts...
If I buy FLM Hybrid bulks I would need 1/8th scale diffs, right? but then to run standard traxxas drive shafts I would need to modify them? Could I run them un-modified with CVD's?
If I bought FLM combo bulks would I be restricted to standard diffs? Is this an issue?
Thats the main ones for now but I'm sure more will be thrown up as I'm new to maxxes, any help would be appreciated, thanks