Nero: When having this same problem with turboBuick t-type center caps due to broken tabs and or looseness of fitting, I found out that 1 or so layer(s) of electrical tape around the lugs, thereby shrinking the clearance between the outside of the tabs and the inside of the mating rim surface, will help retain them without breaking the lugs upon removal. Do not wrap too tight or that in itself will break lugs. I will probably have to do the same on my GTA new rims & center caps. Also, some reproduction manufacturers center GTA caps have more of a tendency to fall off than others. Kirban might also sell those wire frame retainers for the caps, don't remember. I hear that original caps do not fall off like some of the reproductions. HTH.
silicone.. do them all the time for those wheels as well as aftermarket when the bolt holes break in the center cap..and if anyone has any t type centers for a good price, i would like a couple for backups.. would prefer used and i ll silicone them on as well..