Six pack carb mods

I`m aware that the idle mixture screws exist beneath the lead caps, but I was more interested in the rear carb baseplate that has the screws splayed out so they can be accessed without removing the carb. I think I`ll try removing the carb and opening up the screws up a little before buying a new baseplate. The front carb can remain the same. The local Mopar man here was a top tech at the most prestigous carburetor shop for 2 decades before starting his own business. I will start with what info I`ve learned from this thread ,make what changes I can ,and then pass it on to the him ,the expert. From what I`ve read, if you incorporate the metering plate into the center carb it does NOT have a port for vacuum? Thanks guys for all the input.