I have magnuson charger I need to install mechanical gauge where can I hook the hose

 

There should be a little NPT port on the upper manifold beside the blower.

 

I teed mine into the vacuum line that runs to the fuel pressure regulator.

 

Which model do you have? There are different models with different places to put a nipple. If you're not sure which one you have, post up a pic.

 

There are two port on side one for brake and the other for what

 

Ok, look for a small brass pipe plug on the left rear corner(driver's side) of the lower manifold. It's back there close to the firewall. Remove the plug and install a new nipple for your vacuum hose. It's a 1/8" NPT thread.

 

Thanks

 

AK is correct it is next to the fpr port. Just did one on mine.

 

Is there any advantage to running a mechanical boost gauge over an electronic unit? Just out of curiosity?
Sorry for the thread jack. Just got a truck with a Maggie on it and am looking into installing a boost gauge soon.