Adding vacuum ports to old Demon carb

I saw a few of those spacer plates on Summit but they are all aluminum (if I get one I want it phenolic) and only have a big PCV port no smaller ones although I guess it would be easier to add one there than on the carb. You're right too Bruce I'd still need a ported vacuum source for the vac advance. I'm just wondering if anyone has done this before, the newer carbs that have the fittings have them all on the base plate in one spot it looks like it would be easy to do but I'm not about to ruin a great carb I got for a great price.