vacuum lines and the 5 port vacuum switch
 

I have a mostly all original 69 GTO with A/T and AC. The car is not running that great with lag on acceleration and lag at cruise. Idle speed is over 1100. I do have my original qjet but am running a rebuilt 71 qjet that performs the same as the original before i switched it out.
I guess my question is, hypothetically can my car run strong without hesitation and with proper idle speed without this switch. In looking at the factory diagrams on vacuum line placement, my lines are not as they should be. My vacuum advance from the distributor is currently run to the front of my manifold. Is that the best place?
Yearone is the only one of the big 4 i've found to carry a multi port vacumm switch #6754N( this has 6 ports ). Is this the best choice? If i need the switch I'd like to get as close to factory original as i can. Thanks in advance.
Newbee in Training!!:confused: