I don't really see the big problem here. Not to sound pushy or rude, but you must have a tape measure right? And you also know where the screw is, right?
Just measure from the top down, and from the front in to the screw on the inside of the cab, then take those measurements and mark them lightly on the outside. That should be your putty spot <if your still not sure, try using a pin to check to see if you have the softer putty material under the primer. Dig out the putty and unscrew. Yeah it may sound like more work, but you'll probably be much happier with the results. Heck you've gone this far, why try something that may leave an imperfection that will bug you later on <weather or not you can see it>. Then just cut, remount, fill, sand and reprime the repair area.
Also for prying off the glued on piece, I would try a putty knife before a screw driver, the smaller surface area for the driver is more likely the dig into/compress the wood and leave 'divots' that will have to be filled <if your anal like me

>.
Hope this helps
Xar256
