66 Cuda HVAC control problems

67 Dart, I dont have a vacuum test pump.
I have heard about a vacuum tank - there is not one on this car but should there be? Also, does an inline, one-way vacuum valve help?
KitCarlson, is the "vacuum connector" you speak of the 7 pin (a row of 4 and row of 3) one in this thread - http://www.forabodiesonly.com/mopar/showthread.php?t=235757

I found a NOS switch on ebay
http://www.ebay.com/itm/NOS-MOPAR-1...d=100005&prg=1088&rk=1&rkt=4&sd=190792967403&

will this work as a replacement for mine?

Thanks