So, I got all the parts and dedicated today morning for vacuum/gauge install. Did everything except tapping power source, but since gauge mechanical I took car for a ride to see actual vacuum/boot values. First off I have '05 MCSa. Vacuum at idle and cruising were similar to reported in other threads - about 12 at idle and 22 at cruising. But boost values really convinced me that car either have failed BPV or failing supercharger. Pulley is stock, belt was replaced week ago (OEM). As far as I recall from other posts boost should be around 10-13 at red line. It is extremely hard to keep red line on auto tranny, but I tried as close as possible. Under mild acceleration 5psi is normal, under heavy acceleration - it peaks at 10psi but then suddely drops to about 4psi and then climbs to 8psi - but that's it no, more then that. I doubt supercharger is the issue - car has only 59k miles, so I do believe BPV is at fault. I did take it out month ago and adjusted butterfly to close down the gap without sticking. What made me concerned that gasket on BPV felt like plastic and was almost not indented to seal against left (driver side) horn, but rest was working fine. At this moment the only solution (which might not be a solution either) is to replace BPV and as long as it comes out again I might go with DTBPV. Any other suggestions?