Johnny,
1. Take them apart trying not to break each window that's welded in after 38 years.
2. Wire wool to clean all the crap off
3. 600 grade, 800, 1500 grade - fingers start to bleed
4. Autosol - Lose finger prints
4(a) - Accept that you'll never get all the pits out of the frame...
5. Wish I'd never started them
6. Can't get the rubbers to fit - most amusing...Ho Fu&King Ho..
7. Finally get them back together
It's actually not too bad to get them back together - but it takes untill the 6th window to get the technique!
Watch out for the hinge screws - they seem to be the same as the window frame ones - but they all have the ends cut off ! - If you use the Frame screws on the hinges then you will break the glass !
Happy days!