I need to convert the A/C unit from R12 to R134 on my '93 ES300. Can anyone tell me where to locate the service ports. I can only find the high side (red cap). Where is the blue? Also, has anyone ever done this on a ES300?

 

I had a shop do it on the 1992 ES I used to have. Surprisingly, they did it quickly and cheaply. There were very few, if any parts that needed to be replaced. My A/C worked great after that.