the r5gtt carb has been used a few time in supercharger builds and seems to work well,, im going to stick with the glader now as i have bought nearly everything i need charger wise, just need to modify the bracket to fit to the 1.5 engine, play around with pulleys (going to try use the same belt length as the g40 for ease and availablilty but if not longer ones wont be too hard to source), the oil feed return isnt a problem as ive bought an oil filter housing with an outlet so my t-piece will go in there with my oil pressure sensor and vdo twin pole sender and the feed for the charger will go directly in the side of the head. the return is as simple as taking the sump off marking it with an X and handing that and a fitting to my mate. i might just do that with the oil breather or i might plumb it into the carb as it is now see whats going to work best
that just leads me onto the fueling ive just contacted a guy (kris hughes) about his 1.0 eaton'd mk2 polo which uses the r5gtt carb and asked him what hes done to combat the high idle/carb pressurisation thing you mentioned and i am waiting to see what he says but i am thinking of taking the boost pipes over the drivers side so i can fab up something using the throttle cam and a butterfly 90 degrees to the carb butterfly so when the carb is full open the bypass is fully closed and vice versa