Forgott to say! Rockauto ( made by fourseasons ) already sells direct replacement dryers for R134a to most of the cars applications. Also the expasion valve already calibrated and with green O rings for it. The diff is just one number of the pn. I got them from them to my 74, so no need to rebuilt the dryer like the article I posted.

As far I recall but it was LOOOOONG TIME, let say the dryer PN for R12 is 24xxxx, the same unit for R134 was 34xxxx

Or something like that. i can't find the email from the customer service.

Same to the expansion valve.