Just in case you didn't stumble on to the wiring schematic I used - Holun has put it on a site where you can look it up. Works on my bird and worked on his sedan too. Requires the "blue grommet" style of Ford controller with 4 pin and 2 pin plugs.
http://pages.sbcglobal.net/mshum/HoLun/WIRINGSCHEMATICT-BIRD1.jpg
Just looking at your pictures - I'd say the upper rotor shaft of the Duraspark distributor will clean up and drop right down into your "new" rebuilt points style unit. Don't even change the fly weights, try it as-is. A lttle homemade prying tool would allow lifting the plastic keepers and moving the weights to the other distributor if you want to keep them together. The '77 Duraspark on my work bench has the 13L and 18L advance slots - but the weights are both marked "S1B" - don't know where the springs went, they were way too stiff anyway.
Don't worry about machining anything on one of these style of units - just install the Duraspark upper shaft in your rebuilt distributor. If you want to increase one of the advance slots to match the other part - I would suggest transfering the dimensions and carefully grinding the necessary clearance into the donor part.
You will have to enlarge the exit slot for the wiring pigtail - 1/4" rat tail file - and be certain you have a good ground for the black wire. It is attached to the two screw loops on the plastic wire entrance strain relief. Grounding problems are an old service issue with these Duraspark systems - that black wire is coming all the way back from the control module and Ford was "hoping" that the dizzy had a good ground to the block. Don't just hope - make sure you get a good ground down to the engine block.
Steve Metzger Tucson, Arizona