Is it even necessary to replace the Freon 12 fittings with the New Quick Connect 134 fittings?
I pulled a vacuum for 2 hours and wasted 2 cans of 134 the other day only to discover that my Retrofit 134 Fittings Needle valves weren't making contact with the old R12 Needle valves.
Granted I used Pep Boys Retrofit Valves vice the Mercedes retrofit kit (Does such a kit exist?), but these valves actually worked very well on my other Mercedes.
Then I got wise and just used my old R12 hoses and some fittings and just pumped the 134 using the existing R12 connectors in the System.
Questions
1) Does Mercedes make a Retrofit Fitting Kit?

2) What is the System capacity for a Mercedes 85 300D for 134?

3) Should I still replace the Fittings?