low service port location 04 tahoe?

Anyone know where the low pressure a/c service port is on an 04 Tahoe? I see two ports on what appears to be the high side, but nothing on the low side. Thx.

it should be close to the passenger side fender. the smaller fitting is ur low side and the bigger fitting is ur high side. they both should be close to each other.

Thank you. That is what I thought too. However, they are both (the ports) on the same line about 8" apart. I put the low side fitting on the smaller port and it fit. The reading was very high pressure though.