Ah, I see what you mean - interesting idea.
Depends on the bushes I suppose. I'm not sure it's a good idea to put constant stress on them though - that's why you normally fit wishbones, and then torque them up with the wheels back on the ground - wishbone sitting in the natural position to minimise stress on the bushes.
I'll need to check regs to see what I can get away with, and if it's not allowed for classic touring cars, it's just a neat idea to try out on the trackday car.