This comes up from time to time and while I personally have had problems
(dating back to 1977) with AMX and Javelin series with rear air shocks,
here
is a photo below of the damage one caused. As mentioned before,
usually the
upper shock tower on the driver side blows into the trunk, as
while if you
keep it below 60psi you should be fine, however some insist
on more and all
it takes is a small pothole, dip in road, possum or other
critter, even
speed bump, and below is what happens.
The shock
tower on back of a 68-69 and 70-74 was not intended to have that
upwards
pressure and it flimsy to begin with and anyone who has ever gotten
under
one of these knows not much to it, and you can see how AMC grafted the
plate on driver side for the shock tower to basically
sheetmetal.
So when you are considering air shocks because you want big
ass tires, or a
lifted rear or something like that on your AMX or Javelin,
consider below
photo. I have had abuot 4 of them do this to me thru years
and really
difficult finding any welding shop willing to tackle, much less
warranty the
work if you need the 'air shock patch'.
Again, your
results may vary, like my old 68 AMX The Red Death had Gabriel
air shocks
on it for over 20 years and 170,000 miles with zero problems.
This is
off a auction on ebay for a 74
AMX:
Charlie 
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