R-12 A/C System

My 67 Ford A/C quit working 2 years ago due to a vacuum switch problem.
It had run nice and cold the previous several years without adding
freon. I finally fixed the vacuum switch so the compressor kicks on
when it should, but the freon charge is gone.

I read some info about R-134 upgrades, but it sounds like more time/
money than I want to invest. I saw something called FREEZE 12 which is
supposed to replace R-12 with much less work. Can anyone comment on
this stuff? Does it work? Is it safe? Other than fixing any leaks
and pulling a vacuum on the system, what else needs to be done before
filling with FREEZE 12?

TIA,
Paul

>FREEZE 12 which is
>supposed to replace R-12

Lots or R-12 replacement sold under various names is just plain Propane gas.

Larry