DrDiff,
You are off in la la land.
TB EVOI/II are different car from the TB01. Everything about the cars are different. the only thing that they share is probably the shaft drive system. However, their gear boxs are different too.
Hop-up a TB01, will probably be enough for you to buy 2 Evos.
so, why not just get a EVOI/II and race in mod?