The old Chrono is rather nice. If authentic, then that one is likely worth a pretty penny. Its fairly old and uncommon, so I couldn't comment on a reference number.
The second one looks like a 166.020, but it could be an older variant (some five digit ref #). Most of these are labeled as "Seamaster" or "Seamaster De Ville" and the style was made from about 1959 into the the end of the 60's.
If confident enough, you should be able to pop off the caseback on the chronograph without much force, but avoid it if you are not. Parts will be close to impossible to find for a watch like that and you should avoid potentially damaging it. The other one has a monocoque case and you can't easily open it. The movement comes out from the front by removing the crystal and bezel. Not an endeavor for the faint of heart. There are a few tricks to them and I have found quite a few damaged because somebody didn't know what they were doing. If you don't open alot of watches like these, then these aren't really ones to make an attempt on.