civil_wrongz; Be aware there are differences between the trim pieces on the roof line between the roadster and coup models should you need to purchase a replacement.
When removing start with the long roof piece first and pry with nylon trim tools from the back edge at either side corner to get it started.
You should use the 3M double sided Super Strength Molding Tape as mentioned above as it allows for differences between expansion of plastic to metal and helps cushion against road vibration vice a hard glue like epoxy.
The silver color code is XZA. I suggest using a single stage paint vice the original two stage ( color and clear) as the single stage is a little softer and takes the road trash hits without chipping better than a hard clear coat which over time gets more brittle.
There are many threads on this subject. Using the search box in the upper right corner of the forum and clicking on the google option in "threads" option just to the left of the search box will give you results that will help.