A/c 98 Gmc 1500

[nauree]

I just bought a 98 GMC 1500. I live in the south and its been really hot. It takes awhile for my AC to cool the air and I'm not sure if thats due to it being 90+ degress outside. Also, it doesnt seem like my air is getting cold, at least not cool enough for me. I turned the AC on and checked under the hood and its kicking on and off every few seconds. I, for the life of me, cant find the low pressure service port to check my freon level. Can someone give me a detailed description to where it is located? I'm not talking about "its on the compressor" type description but more like a "its on the passenger side near the front under the whatever". Hell a picture would be awesome.