I am in the process of installing a 1952 caddy power steering in my 51. I understand now why GM stopped retrofitting these in 53. Not too difficult but not so straight forward. Even though the 52 box fits right in a 51, you have to move the horn contact to the steering column, ( I'm using the 52 column as it's easier)you also have to move the front brake line as well as move the oil filter housing. So far, the most difficult part was obtaining the correct hoses. I will post pictures when completed. Also prior to getting my hands on a 52 steering box, I had bought a 54 and rebuilt it. It however did not fit. It did bolt right up to the frame but the hose connections did not clear the frame. So I have the 54 steering box posted on the popular auction site. Keep you all posted.
Breaking down to rebuild 1952 power steering unit. Seals failed and grease mixed with steering fluid. Very common.
My original 1951 manual steering box I rebuilt.
1952 power steering: New bearings, o-rings and seals. Going back together.