thanks for the reply...i picked up a spare 3.54 rear from a 85 turbo Z in decent shape($80}...i have fitted the PG inside the open diff, only after grinding the large spider gears and the PG itself..i ended up using the cutting wheel on my chop saw as a grinding stone of sorts...it worked decent but took awhile to get it to clearance fit....i tried contacting the makers but their website is extinct,,,only a facebook page and the phone # is a voicemail deadend....a question for anyone who installed this device...when the PG is slipped inside the carrier unit, and the clearance between the PGand the large spider gear is set tothe recommended .005, should you be able to spin the spider gears freely before pulling the locking clip off the PG to release the spring tension of PG blocks to large spider gears?? yes, a OBX is next!...thanks, mike