Alright, a quick revisit to the 686-6.
I got my Wheeler Digital Trigger Pull Gauge and a Wolff Power Rib Type 2 Reduced Power Spring Kit. The kit includes the Reduced Power Mainspring and 3 different Rebound Springs. Not knowing the history of this revolver, I also bought a Standard Strain Screw and an Extended Strain Screw from Wolff. The “as bought” strain screw is visually shorter than the new Standard one from Wolff, but I did not make measurements.
By the numbers:
As Bought Configuration:
Double Action, 5 pull average: 11lbs - 7.1oz
Single Action, 5 pull average: 4lbs - 11.0oz
Wolff Reduced Power Mainspring w/as bought Strain Screw:
Double Action, 5 pull average: 7lb -11.1oz (33% reduction)
Single Action, 5 pull average: 4lb - 9.9oz
Subjectively, the firing pin “shoots” a wood pencil out the barrel about the same with either mainspring. Since my objective is to reduce the DA trigger pull, I don’t expect to experiment with the rebound springs, but knowing myself, I probably will 
Now I need some range time to validate no light primer strikes. If there are, then I’ll start swapping out the longer Strain Screws for reliable firing.
Edit: I guess I should of said why I want the DA pull reduced. It’s pretty simple, I have Dupuytren’s Contracture Disease in my hands and I really can’t handle a 12lb pull for very long any more. I am currently recovering from my 2nd surgery on my dominant hand … so range testing will be hopefully in a couple weeks.