Sapper, it would certainly be interesting to see what you can pull off ..,erm put on, since you have the plastic piece.
I would carefully clean the contact areas with a wipe of acetone, as it will slightly melt the plastic and remove oil and grease residue thoroughly I have heard.
I would use a new pliable piece of vacuum hose so you don't have to use as much force to get it on and a film of oil to assist further in getting it on without breaking it would be a good idea after the cement has had a good amount of hours to set.

It should work as there is no real load on it once set up.
Best of luck.

Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!