Vacuum source for charcoal can

[bowhunterwyo]

I have a 79 with a AMC 258 i6 / 4.2l and a weber 38 I have the pcv and valve cover breather going to my carb. I have the carb bowl vent and the tank vent going to the charcoal can, I have no idea where to get vaccuum to the can for the can function, my thoughts were to get a newer model pcv valve with the t on it, and take that to the ported vacuum spot on my charcoal can. The pcv is already under vacuum because I got it hooked up to the spacer on my Weber. Any thoughts

 

[Sasquach]

T into the ported vacumm line from the carb. The manual for my 78 shows it from the spark port(above the throttle plate).