My apologies to all, I was away for the weekend and was just able to look at the replies today. Thanks to all for your responses.
So OK, I get it......I would be converting from R-12 to R-134 if I change things out. Some asked for more info on the model of the car:
1984 300D Turbo
This friend is the realtor that sold me my house, she's has been wonderful to my wife and I so I want to help her out.
Thanks again to all.........