My 95 gmc serria is in need of some Freon so I went out and bought me a can of that ac pro. Can someone tell me were my low pressure port is. I was thinking it was the one closest to the canister at the fire wall on my passenger side but I've read online were someone said that's the high pressure. Any help would be appreciated I got a 300 mile trip tomorrow in 95 degree weather. I don't wanna die from the heat in some stop and go traffic.