I have a few vehicles, a Benz being one of them, that I have changed over. I have a vacuam pump, guages, etc.
That said, I agree with Benzmac. If you can fix the leak and stay with R12, you will be much better off.
From previous posts and online conversation with Benzmac, it's obvious that he has massive experience in both changing systems over and repairing them to stay with R12. These are real "words of wisdom" you're getting from him. Their very valuable words of advice, but you're getting them for free.
'84 Euro 240D, 523K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in