94 Skylark low pressure port location?

I was getting ready to charge my 94 Buick Skylark 3.1 with some R134a but can't seem to locate the low pressure port. I have charged several systems before on different vehicles no problem but just need a little help on this one. If somebody happens to know where it is located i would appreciate it. Thanks

Are you sure this is not a R12 system? Just double checking.

Anyways, on a typical GM car with a 3.1L V6, Vin "M" such as yours the low pressure service port is probably located at the output of the compressor on the line with the bends so maybe that is why you are having a hard time locating it. Accessed from below. The pic below shows the location of the port with the convenience of the compressor being removed for viewing.

http://i5.photobucket.com/albums/y186/lizzywiz/port.jpg