This has always been a problem with aftermarket collars it seems. They make them too good. You could try to find some old used up originals or grind a bunch of metal off the short end to reduce the dia. Its a "do what you have to do" kind of thing. You can still drive the car if you block off the the fan shroud outlets until you can fix things.  Elect. tape, rags,etc..  will not "get it". Most of the time ends up in the fan.