Kris,
The flip switch used isn't electrical, it's a pressure switch in the actuator line. Low is closed so all the boost goes to the actuator, then high bleeds the pressure off so it takes more boost to operate the actuator. There are also bleeders that thread into the vent of that switch so you can dial in the higher boost even finer.
I have two BOV's on my rear mount Apex, similar to the setup for an RX1, welded in nipples plumbed off the intercooler before the carbs.
Full Power Performance (FPP) supports and sells replacements and upgrades for all the old Bender rear mounts. Highly recommended is the upgraded flex joint in the exhaust before the turbo exhaust flange, if yours doesn't already have that.
Do some searching on here for Bender Rear Mount and you'll find enough to bring yourself up to speed on these...
Mauri
