I have a 2002 XJS and the front fender emblem came off. It's the part that sticks to the silver piece that is actually touching the fender.
So basically I have a thick gel sticker that came off.
How should I re-affix it to the silver base? What kind of glue or 2 sided tape should I use?
Thanks. See pic.

 

Use 3M double sided sticky tape (or a "copy" of that kind of tape). It comes in black and transparent. I'd go for transparent.
You'll find tons of it on the usual cheap online shopping portals.

 

I use 3M Plastic and Emplem Adhesive, Part #08061

 

Make certain to adequately sand smooth and prepare the mating surfaces or
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