re: unhooking
1) When on an uphill slope, drive the toad about a quarter inch (or so) into the towbar - enough so that when you set the park brake on the toad that the toad doesn't rock backward enough to undo what you just did.
2) take the towbar's breaker bar to the release buttons on the towbar arms.
the towbar arms should now easily release from the baseplate brackets.
When the MH is on a downhill slope, repeat step 1) but put the toad in Reverse and back away from the towbar about a quarter inch in order to relieve the pressure on the baseplate brackets.