[Dimis]

Far be it from me to offer any safe advice. I can't even complete my 5year old's lego car in the same time as you've built this car. But if I may can I ask this dumb question?

If you are building the chassis around the engine and drive train, how do you know you'll have enough clearance to pull the engine, (or box etc) should you need to in the future?

I'm thinking you've thought about this and other things, so excuse my ignorance.