Ever since i started working on airframes , i was repeatedly told no sharps to be used
The best way to apply an adhesive fason is with water ,
the fason can then slide into your designated area.
Then useing a small plastic spreader or fason roller squeeze the water from under the edges
From centre outwards making sure no water or air is still trapped underneath (it definately works)
seriously you may think a small pin can not cause damage
but it can and will .
over pressure may scratch the airframe surface or if its a material surface (paint and dope) can even make a tiny hole.
you may think im over reacting but ive seen it all?
metal objects no matter what, cause dissimular metal corrosion
And on the material side of airframe coverings, a tiny hole in a sealed dope system is all it takes to cause unforseen damage
Re/ the stripper causing problems, paint removers are very nasty indeed but they do the job which is required
never think you have masked for stripping ( excuse the expression) perfectly,
always check and re check, ingress of paint remover and the damage it can cause is horrific especially around windows and undercarriage areas.
Can you elaborate a little on the uv effect and im sure i can help?