Right, first off I'd remove the hi/lo boost solenoid, it can be unplugged and taken off no issues this will also remove a restriction. I'm guessing the A/C has been removed, if so you can remove the vac hosing to the right of the intake manifold, and un plug and discard the sensors. Dedicate one of the spare nipples to the boost gauge, then plug the hole left in the T piece or remove it and link the pipes up or replace the pipe, or remove that dump valve (That could be giving you some issues). Is there a boost controller? How to remove the boost solenoid (restricts 1'st and 2'nd) http://www.toyotagtturbo.com/forums/showthread.php?2277-Hi-Low-Solenoid-Bypass