Normally yes but becuase of where the turbos will be sitting and where the pipes are running there is going to be a very limited amount of space to fit everything. Doing it with the motor in will let us know where we can run the hot exaust pipes without melting anything. It also is giving us a good Idea of where we are going to have to re-route alot of the hoses and what not. Without even having the turbos in yet we can already tell we're gonna have to move the heater core hoses so even though the fab work will be alittle harder with the motor in, it gives us a good picture of where everything is being layed out.
I'm certainly not the first person to remove the crash bar, I think it will be ok, if not I guess I will have two sides to a really fast car