[BABU]

gun is a stock G&G pm5-a4 (mp5 a4) with the clear upper receiver, not the sport line version though

so i just got my guarder clear rubber set and shredders concave spacer, and am working on installing it now.

i already took a knife to the guarder clear and sliced off the nub and the alignment line for the barrel so that i could twist the rubber around and have a clean un cut patch of rubber protruding into the barrel through the hop up hole

i also cut out a small square off my old stock hop up rubber so that i could place this piece either under or over the shredders concave spacer so that it would protrude far enough into the barrel to be effective when the hop up is turned up

i started placing everything together and lining it up when i had difficulty pressing the hop up adjustment into the barrel, so i took the rubbers off and just tried fitting the shredders concave spacer into the barrel through the little square hole, it wouldn't go through, was too tight of a fit to make it all the way through the little square and into the barrel

so i realize if i install everything the hop up wont work, any tips??
should i be modifying the shredders spacer or the barrel to make it fit in??
i was thinkin about maybe takin some sand paper to the edges of the spacer and sanding it down a bit, seeing if it would fit then

has any1 else had this problem before??? and how did you solve it???