It is much easier to just use the correct add on clip.
Then too, it is possible get the retainer to stay on without a clip. I took me 4 attempts on my '77 Ramcharger before I finally figured it out.
YMMV so no guarantees........
What I found is the original retainer, if in good shape, is better to use since it has been formed to the cup already.
Upon removal, only bend 4 of the tabs on two adjacent sides outward just enough to lift the retainer off.
For retainer install, bend
the other 4 tabs
(A) inward slightly. This will create some tension for assembly later.
Test fit the retainer to make sure it will fit over the cup. You may need to open the outward bent tabs
(B) a bit more.
Before crimping
the B tabs back in, make sure the seal is in position and the retainer is held down.
Crimp the
B tabs down evenly
without your crimp tool pushing on the tabs
(A) that you bent inward.
The blue lines indicate crimp points. As the
B tabs bend in, the
A tabs bend outward creating the tension needed to hold the retainer.
My '69 no clip.......