I broke down and did it tonight.
The before pic
Marked up and ready to go. I traced the inside diameter of the clamping ring.
I cut the outside of the trace ring and with the natural stretching ability of the material It was enough to slide the fitting through.
I cleaned both surfaces with carb cleaner. Then put a layer of silicone on the fittings flange and pushed it through.
I out a layer of silicone on the outside of the bag before clamping it all down.
I will try it out in the morning and maybe time it to see how much time I actually save with the jabsco added.
It was scary cutting into my precious bag but it actually went fairly painlessly.