At your local mustang store...they sell a small rubber sealed sleave...that fits into the hole in the trunklid.
1. look at the open hole...does it look like it has a liner in it? if so then that is the original sleave and it will need to be removed, (i used needle nosed pliars)
2. trim the rubber in the new sleave (i used nail clippers)
3. Insert the mounting sleaves into the holes (no bad commentary from you aussieitem!
4. gently push in the chrome letter.
I found new letters were cheap. and looked good. and for the first time in 10 years I'm driving a Mustang instead of a "m'stazg" And here I though I had a unique russian ford car,....
1968 Coupe, 6cyl Std, Bench Seat. Driven through 10 years of College.