Here is another little bit of info regarding AC lines. Recently, with Jeremi's help, we put a mach 1 engine in my friend’s 93. Since the serpentine belt routing was different than the mark, it forced us to use the mach 1 ac compressor manifold to avoid interference with the belt. Unfortunately the mach 1 lines are smaller and in a different location. The AC system has been capped off until we were able to figure out how to mate the different sizes. We found a place,
www.coldhose.com, that makes ac hoses to your specs. On the low pressure return side of the AC pump the mark line and spring fitting and barrier hose is a #12 size and the mach 1 side is a #10. The line was about $50 to have custom made. We ordered it just a little too long the first time around so a new one should be arriving any day now. If anyone wanted to try a high pressure hose without the muffler this would be the place to get it from. The high pressure line is probably a #8.
Also, the sizes referenced on their web site for all fittings and hoses are #6, #8, #10, #12, etc. They have a chart that correlates those to an SAE size. They COULD NOT tell me what the SAE size was referencing. I wanted to know if it was the ID or OD of the line, the fitting, the flare, WHAT was it? I talked to a few different people there and asked them to take a fitting off the shelf and measure it to figure out what I should be measuring on the car. This was too much of a complicated task for them and they told me they only deal with old cars and they couldn't help me. I told them the car it was going on was irreverent (and it WAS old), I just need to know what the dimensions reference! With a little bit of digging a found a document online that told me those measurements refereed the ID of the line before any flares or fittings.
Summary: Know what size fitting and hose you need from coldhose.com because the guys on the phone don't have a clue and won't find out. The product seems good though.