so its the line right off the BPV right? thats the correct spot. autometer isnt really that great. i had same one you had and it would bounce 5-7psi. i used a pill from the OEM EBCS and it dropped it to 2-4psi but still hard to read. id get rid of it and get the electrical Prosport that has a white needle and red background so it looks the same as your OEM gauges. electrical is the way to go. at only $70 its only $20 more than yours.
till you get that or some kind of EM no one will really know if its right.
get the tactrix 2.0 cable for $180, download free rom raider and boom you can start logging and reading you ECU.
Scott-2011 WRX 335HP 394TQ 93 VF52!