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Vacuum issue erratic idle problem

What is it that is going on that you are trying to fix? Is it HVAC related? Engine not running correctly related? Are you trying to locate a leak? etc...

I guess a good place to start with any of it would be the Vacuum Tree located on the driver side of the firewall. Another place is where the vacuum lines come from the rear of the intake. Then from there follow them to there respective locations.
A couple go to a little diaphragm looking thing then go through the firewall into the cabin to control the HVAC.
Another set goes to the EGR system on the passenger side on the engine.
One way to find a vacuum leak is to spray some starting fluid around the vacuum lines while the engine is running and listen for a change in engine speed.

Also if it's not a vacuum leak causing the erratic idle; check the Idle Air Control valve. It may need cleaning or replaced.
Hey bro just found this 1 on advanced auto parts is this the 130 amp alternator needed for the Foxbody upgrade it says for a 94 mustang but seems to be same i looked at on lmr site i know ill need the 4 g cable and fuse block also i think thx again Screenshot_2018-05-10-21-47-42.png