Have you blasted the surfaces inside of the dovetail channel free of all debris with brakeklean, etc?
Now the obvious question is, does this vise presently work in a satisfactory manner?
The last five vintage vises I’ve dealt with I’ve purposely never removed the “nut” which is what you’re calling the dog…if it doesn’t need to come out, or shimming to finesse the fitment of the dynamic jaw/slide, what is your worry?
You don’t need to disassemble it, just clean around it, and clean the thread bore as it sits.
If it isn’t broken, you don’t necessarily need to fix it !
I may have entirely missed the backstory of this vise, and if so, I’m sorry to sound presumptuous here. Is it broken or fine?
Thank you for the update!
Shawn