Muzz, print this out and take it with you.
172 and un-cup'd 182 shockers have a design flaw in that they can't be manufactured reliably.
It's a known fault and a common one, if only one shock has burst, dont be tempted to replace the opposite one so as to 'match new to new' as the chances are the new replacement one will burst too.
It's only a matter of time before mine go again. My June 04 182 has had 9 shocks in its lifetime, ridiculous!