Getting that factory AC going again.

[ah_5500]

I decided it was time to get the original ac on my truck going. Everything is there and there are no leaks. So we pulled a vacuum and charged a couple cans of 134. I thought and partially assumed it had been converted from r12.
How do I know if it's been converted? How do I convert it if it hasn't?
The air got cold but pump started sounding and acting like it was about to lock up like it needed oil. School me on oiling please.
Lastly, the pump didn't cycle. It ran without shutting off.
Thanks in advance!