Adding a 2nd Ademco 6128 keypad to Vista 10SE W/E2

["Dan" <none@xxxxxxxxxxx>]

I recently bought a house with a Vista 10SE W/E2 alarm system.  The system
has 1 6128 keypad located in the house.  There is a "semi-detached" garage
which has a motion detector.  I want to add a 2nd keypad in the garage.  I
have a  new 6128 mounted in the garage & connected & have run the wires into
the alarm box inside the house.  So far so good.  I understand all I need to
do is connect the new pad in parallel with the existing one, to terminals 4
(black) 5 (red) 6 (green) 7 (yellow).  Seems simple, but I have 2 concerns
1), the label in the alarm cover says "Remote keypads MUST be programmed
with a #5137AD or 6139.  It need not remain in the system... After
programming, the system can use: (a bunch of keypads including the 6128
@30ma)."  So do I need one of these other keypads   (#5132AD or 6139) to
program the new pad?  Also 2) if all I need to do is connect the keypad to
the correct screws, is the alarm company going to "freak" when I do this?
Do I need to call them 1st (which I'd prefer not to do) or can I put the
system in some "stand down" state while I connect the keypad, then
re-activate it after?

TIA

Dan