Both flights operate with a 762 on the rest of the days.
Negative. It is always a 767-400. In the CO timetable, 764 is the 767-400 with 35 BF seats used mainly on Europe routes and the 767 is the 767-400 configured with 20 BF seats, also known as the Micronesia configuration. The 767-200 is listed as 762 in CO's timetable.
Here's a factoid, on the flights to Guam, CO 1 and 2 on ATC, operate under the callsign "Air Mike", as in Air Micronesia. Sometimes the pilots will forget and say "Continental, 1 / 2 heavy..." then quickly correct themselves, it happens quite often.