Nope, either side is fine. Same goes with the carb connection, although I don't recall my Eelbrock having a rear port.

 

I found out the rear port is for power brakes! I will just plug that and use the front PCV port!

Thanks for the info! I cant wait to get this running again! 2v to 4v plus a stealth intake should really change the feel!

 

You can use any big vaccum port..Don't feel that the rear port is just for power brakes..You will probably get a cleaner look if you go from the rear port and over to the passengers side valve cover like the factory did it..

 

Really!? I can use the rear port on the carb? I would like to hide as much as possible. The front port is labeled for the PCV that's why I thought "only" the front.

 

Hi,
The proper location is the front center port. Those on either side are dizzy vac ports.
A side benefit of running a good PCV system is it reduces any tendencies for the block to seep oil, as well.