For the goal in question I would start the taper with a slightly reduced volume the last big weekend (chop about 25% of the volume) then do a normal rest week which should be a little more than 50% of your previous weeks volume. I don’t like to change a ton in the make up of the taper week just scale the whole thing down.
For returning to training from a Rainier it should look about the mirror image of the taper to ramp back up. That said depending on how your trip goes and your recovery path you may well need more time for rest on the backside.