Okay, I have a few observations that you may want to consider.
If those knobs don't have the recess for the trigger sleeve then you'll see the rather unsightly naked shaft. Worse yet, that open area makes a hell of a pinch point when you pull the trigger. This is experience typing this. I used a plain ball on one of mine and I had blood blisters to prove it. It sucked.
I don't know if it would be much better if they machined the recess for the trigger sleeve. It would be a bear to orient the pattern correctly. There would be no way to get a wrench in there to tighten a lock nut. You'd have to use shim washers instead.
I'm not saying it can't work. I just thought that you should know that before jumping in.