Is there a proper way to mount rear offset BUIS from the distance of your eye?....I've heard that you should have the longest sight radius as possible between front and rear BUIS, but heard nothing about distance of eye to the rear BUIS. I have a Bushnell 3-12 scope on a Burris P.E.P.R. QD mount. If I mount the optic to the upper as far back on the rail as it can go, I get good eye relief and cheek weld placement no matter how many times or how fast I shoulder my rifle.....but then the offset BUIS needs to be placed further forward on rail. So is there a proper way where the offset BUIS should be mounted from the distance of your eye? With the offset BUIS mounted towards the rear of upper rail, the scope eye relief is now further away and there is no more room on the scope tube to move it further back closer towards my eye. And the reason I have offset BUIS is cause the scope is a 3-12 so anything closer becomes a blur and having BUIS is easier to transition to for closer shots. My vision is already bad and old so anything useful hitting my target would be helpful and would rather not spend money for a offset mount and a micro red dot.