Thanks for the good info. It is a mass air (Im assuming as i have a MAF). It currently has a blow off have connected to the pipe between throttle body and SC. The blow off valve In turn has a small hose leading into the air intake manifold.No boost controller is necessary, that is strictly a turbo thing and will not apply to a centrifugal supercharger.
I would recommend a mechanical boost gauge, something like this http://www.summitracing.com/parts/atm-3401/overview/
This would be plumbed directly into the manifold after the throttle body
Is the car Mass Air or Speed Density? If Speed density you can use a traditional blow off valve and vent to the atmosphere, this would only be needed if the blower is producing more than 5-6 lbs of boost
If the car is Mass Air you MUST use a recirculation valve when boost pressure is over 5-6 lbs ( blow through mass air excluded ). This would get plumbed between the discharge tube and intake tube and recirculates previously metered air.
This is what I would recommend for applications that see 6-12 lbs of boost 8D001-004 | Vortech Superchargers
The only way to adjust the boost would be by changing the pulley on the blower or the pulley on the crankshaft, you must also be mindful of impeller speeds. Typically I do not recommend changing any pulleys on the SN 89,93,2000 blowers as they don't withstand the torture that today's blowers easily handle.