Low side A/C charge port
 

I need to convert this low side port to accept the newer style quick disconnect r134a adapter.
I bought 4 and none fit( they are all to big)
Where can I get the correct adapter
Please help....thank you

I have had good luck with obscure A/C parts with these folks on a few projects. If you can't find an adapter locally, might give them a call.
https://obsoleteair.com/

Do you have a local NAPA? They're typically quite helpful. And actually, if you know what to look for, the local generic parts stores (Autozone, O'reillys, etc) also carry a bunch of fittings. My local guys will even typically let me take stuff out to the parking lot to see if it fits.

If you're looking for the low side adapter that screws on where the r12 manifold hose would connect so you can connect the r134a blue quick connect fitting, then this should work. I purchased the low and high side connectors. Low side, 409903 and High side, 409902.

https://www.napaonline.com/en/p/TEM409903

Also these connectors are universal. All low side are the same. Smaller than high side. The high side is between the compressor and the radiator (condenser) low side is after refrigerant leaves the interior and is coming back to the compressor. High side is hot. Low side is cold.

Here's what I got for my 78. https://shop.advanceautoparts.com/p/...E&gclsrc=aw.ds

https://cimg2.ibsrv.net/gimg/www.cor...1593c35d20.jpg