Thanks for the hints.
I check for propper Zero and straightness before i drill.
After the Initial Setup, that took me like 1h for perfekt allignment, IT seems to stay true.
The only "milling" at the Moment is the Slot at the but of the ILF Limbs.
Bur this alone, is an absolute gamechanger compared to Drilling this with jigs....
The Vice was 100€ it does the Job, for the start.
I'll Upgrade this in the Future.