Thanks for the info guys. Especially Rick W, your comment was especially informative. Good to know that the hot ammo thing is a myth.
-I was aware that the handle scales would need some trimming when I ordered them. All the same it was still more than I expected. I regret removing as much material as I did, and I got a bit of a split going in the wood...

The left side scale was a pain fitting to the safety mechanism.

The job didn't go as well as I wanted it to. If I ordered another set I think I could do a much nicer job knowing what I know now. -But at least these grips will be still usuable for shooting.
After I got them fitting the gun good, I had to trim the outside for ergonomic reasons. Where the thumb wraps around by the safety was sticking out too far. I lost some diamond texture but it was more important to me to be able to hold it comfortably. -Then I gave it a nice dark red stain.

I'll include some pictures, having grips makes a big difference for the gun, and despite botching the job a bit they're still quite usable.
Lots of cutting was required and everything was effected. I had to trim to make the safety turn off all the way, bit also a fair ammount of trimming to make the mag release work properly. Even the the magazine face rubs against part of the inner handle that needed to be trimmed away. Lol, even the little Luger tool needed trimming. I went to town on it with a rat tail file before the hole could even connect with the spring button on my MecGar.
Luger doc I am definetly interested in ordering some springs. How does it work to order and do you ship to Canada? I also need that rear sight and I'm interested in the magazine stuff. What is that "mid axle retaining pin" you say I'm missing? Is that for the magazines? I'm thinking to order one fancy wooden bottom and an aluminum one. I might order some better handle scales too so what have you got?