Have you thought about having the holes oversized and using eccentric bushings on each end? That way you can adjust each end and you could focus each beam to any focal length you want.
Honestly I didn’t bother reading much you posted. I had a hard time getting past your attitude. I’ve been working with electronics for over 20 years just not with lasers in particular and working daily with voltages over 10k dc. I’m aiming for 2000yds illumination and didn’t see that happening...