I've got a 142 from 1972 and was doing a check up today and have a few questions.

I was looking at the rear wheels and relized that the rear oil seals are leaking. I want to replace them but am a bit confused about the process. I have a hanes manual and sometimes I get confused. My rear axel is actually frome a 73 145 and I think I messed up a few years ago and purchased seals for a 72. Are these the same? In the Haynes manual they talk about cutting the retaining ring and than replacing it. I also have 2 seals and only see one on the half shaft, the one between the bearing and the rotor end. where is the other seal? Please help.

My next issue is with my cooling system. My overflow had fluid in it and the engine was completely cool. I removed the radiator cap and the radiator was full but slowly the fluid level went down until the level was just above the opening for the top hose. Is this normal? do I need to check anything out? I topped off all of the radiator and overflow.

thanks
chef blue