Yeah, what custom68 said...What did you start with? There are two sized ports coming off the top rear of my Sanden 508...one smaller than the other. What sizes do they call them? Does the larger size go directly to the accumalator, which also has the larger size port on it? Does this line need a service port plumbed into it? Then does the smaller port exiting the firewall go directly to the condenser thats forward of the radiator? Which port on the condenser, top or bottom, or does it even matter? Then a line returning from the condenser to the small port on the Sanden compressor? Does this line also need a service port? I'm at the A/C & exhaust stage & need input. Thanks in advance. Gar