If QD is not a deal breaker then Badger Ordnance has their 1.25" High Scope Rings which will work for the Mark 6. I had a similar project in mind so I called them and that is what they recommended due to the size of the Mark 6 objective.
I'm an ADM guy, and for personal reasons... I always prefer the ADM " dual " lock as oppossed to the single latch ! Some of their " recon's " have a single lever lock down. I have 1 on my " surgical " Match Colt 20". Only because I picked 1 up one time and didn't want it on a harder hitting .308 !
( " more is better " Right ? ) at least the ALLY BankTV commercials say's so !
I have ADM of most of my stuff, there was only 1 mount that I worry about and that was on the Trij RX34, the zero shifted on me, caught it the other day however ..... I also have fed about 3k+ of rds thru that thing w/ my slide fire stock. it has taken some serious vibration !