older mitsubishi Mr slim

hello, lost my journeyman refrigeration and air-conditioning adviser ( dad died at 96y/o)
Have a Mitsubishi MU-09CW he and I installed @ 15-20 y ago Appears only access port is on the high pressure side. Is this true?

source https://hvac-talk.com/vbb/threads/2242455-older-mitsubishi-Mr-slim?goto=newpost