Alarm System Problem / No Start

I parked my truck on an incline facing nose down a
couple of days ago with easily more than 50 miles
until empty.  I went to start it the next morning only
to see the fuel gauge say it was at zero miles until
empty and no dash lights working.  I had full
battery power which I confirmed with a multimeter.  
I tried a second set of keys to see if a different
remote and key combination might solve the issue
and this made no difference.  Then, I disconnected
the negative battery terminal and reconnected it at
which point the dash lights were working again and
the truck started right up.  I searched online and
thought it may have been a problem tied to the fuel
pump and the truck's computer not registering I
had enough fuel in the tank because I had been
parked on an incline.  A few days later, my wife was
driving home and both the speedometer and
tachometer stuck and the dash lights went out
again.  After turning off the truck, it wouldn't start
again.  Only an airbag light was showing on the
dash and I still had full battery power.  After
speaking to a parts store employee, he suggested I
try using the remote to manually activate the alarm
and then turn the alarm off to see if that would
resolve the issue which it did, the dash lights were
working again and the truck started right up.  I still
don't know what the problem is but so far at least
have a work around to reset the alarm system.  The
Ford dealer said it might be some kind of
communication problem with the alarm system.  
I'd like to resolve the problem myself if possible
rather than have to take it to the dealer.  Any
thoughts or ideas would be appreciated.