BabaYaga

Another approach could be to use a pair of small glass lifters to create the slight curve from inside.

The alternator make appears to be CAV (says so on the back side). Maybe something like this? Alternator 1977-1983 (75 AMP) (UE41719SXR)

I agree with everything you say, but my comment on the risk of chafe on the rope was made with regard to the OP's proposed idea with a...

I was rather thinking of chafe on a rope that passes other stones or rocks on land or in shallow water before reaching deeper water. Of...

I think there would be a high risk of chafe on the shore line from rocks and stones etc in the shallow water next to the shore...

I have the series 32 tricolour only (so may not be identical to the 34), but on this the locking ring movement is quite limited, far...

To which can only be added that rules in Sweden and Finland are even stricter, as discharging toilet waste into the sea is unlawful...