05-10-11: Gadfly
Do not use the guard when removing the body. It will only get in your way. Easy does it, slow and steady, and you will be ok.
I've nuded a few 103R's and have always kept the stylus guard in place while cutting the glue points. This way you can place the cartridge cantilever down on a bench while you cut the glue points in the seams. Some firm pressure is required when cutting and it would be near impossible to damage the cantilever with the guard in place. I strongly recommend using the stylus guard while cutting.
Once the 3 glue points have been cut - and you can move the plastic shell freely - then remove the guard so you can observe the cantilever position while you carefully pull away the plastic shell.
Emorrisv, I live in Australia but if no-one more local to you can supply a stylus guard, drop me a message and I'll post one to you.