70's era Metal Ceiling Specs and R & R (Remove & Replace) Facts

[Distantdrummer]

OK I don't have any facts on: And there are few threads on this subject that I have found or recall seeing. Remember I am seeking 70-80 era info.
So I ask:

• what is behind the ceiling,
• what is space to roof?
• does insulation tend to settle or stay well in place up there?

• what holds ceiling up?

• how to remove it,

• replace it,
• is this a monumental task for single person?

• what size the panels are. exact please. Mine is a 31' RB.
• anything special about the edges of the ceiling panels such as crimping etc?
• Is the channel along each side still available?

• Is there a better channel alternative?

Any direction or ideas or just useful conjecture would be appreciated.

thanks