The plunger spring is too long to fit as is. I cut mine off even with the extractor spring.ramshackle used a 1911 plunger spring. there are several manufacturers of plunger springs, or atleast several people selling them with diffeent brownell's part numbers. one of the numbers is: 969-000-124. price: about $3.50
apparently with this one you just drop it inside of the factory spring. revchuck seemed pleased with the results.
Shot a USPSA match with it last weekend. No problems whatsoever (not including my shooting ) using my handloads and mixed brass.