You can, but the result won't be very nice. The plus scales are a bit thicker than regular scales cause of the pen so if you just file a groove, the plastic pen cap will protrude above the scale and the scale will be very thin in that portion.
Agree with all the potential issues, but not the ‘wont be very nice’. I did one and the pen tip can be modified for a flush fit, if desired. I left the tip thick and I can grab the pen without removing the knife from my pocket. The back shield scale is a mid-‘90s Marlboro Troubleshooter mod. The other knife is a ‘05+ Champion Plus with a short tweezer mod. .
Thanks for the pics kamakiri, they definitely help! I wouldn't mind having to modify the end of the pen to make it fit a bit more flush. I think I'll find a set of standard scales that I have laying around and try it on those first.
It seems like Felix might have been stalking this forum:
Good luck with the project . Nice job kamakiri.