To my knowldedge the clutch and flywheel are the same. Here is one difference I am positive of. If you try to keep the point distributor you may likely have to swap over the intake and carburetor. Reson being in 66 Ford 240/300 six's used the Loadomatic distributor and carburetor combination. These parts can only be used as a matching set. If you mix and match either distribtor or carburetor with non Loadomatic parts you will not be able to achieve proper vacuum advance. Furthermore you will drive youself crazy trying to figure out why.

The 77 model you have probably has a Carter YF carb which is much superior to the stock 66 job. The 66 probably has a nasty Autolite 1100 or maybe a Holley if your lucky. Most folks are going to say go for the Duraspark ignition so all you may need to do is drop the newer stuff in and figure out how to wire it up. Somebody here can help out with that part, I hope. I prefer an original apearance so I still use the points. If you would like to keep the original look with the benifits of electronic you can install a point distributor and Pertronix electronic conversion. A lot of people are doing that. I am considering it myself. Way better than a bunch of cut & spliced wires.