Hey guys. Blower for LS1? Need height estimate.

Can you tell me a very rough measurement of an 8-71 Chevrolet Blower for a standard small block? Mine is a LS1 (should be very close to the same height?) and I'll be going with the 8-71 BDS. I'll be running a pair of TBI's that look like Demon carbs (found a place that is making sleeper carbs....with injectors). I'm trying to decide how much to open my firewall up for clearance. My motor is set back into the firewall a couple inches. I would appreciate it greatly.

Thanks,
Dave