Finally replaced the fuel pressure regulator. Not as terrible as I was expecting, but definitely not fun. Surge is gone, and I’m getting accurate and consistent balance rates finally, so it was well worth the time.
2005 GMC Sierra 2500 HD SLT 4x4 LLY
PPE Xcelerator Standard (Volant) 160 hp tune, EGR block ,Rudy's Performance Turbo Inlet, CAT filter, Allison Deep pan, Trans Go Jr., Edge Insight CTS, Magnaflow downpipe, Diamond Eye cat delete and straight piped