Strut cartridge replacement question

[Jeff Wozniak <JWOZNIAK@KENTVM.KENT.EDU>]

Hello,

I am planning to replace the front strut cartridges on my 84 Coupe GT
this coming weekend.  I will also be replacing the strut bearings. My
question is regarding the removal of the old shock unit which is built
into the strut itself (it's not a cartridge).  My Bently manual
shows that the cap which secures the old shock unit into the strut
requires a special tool.  The tool is basically like socket except that
it fits INSIDE the cap (the inside edge of the cap is hexagonal.  The
manual indicates that this cap is on pretty tight and that the tool is
necessary.  My friendly Audi dealer tells me that this "socket" tool
can be had for only $95.  If that weren't bad enough, the tool will
only be used once as the new cartridges use a different style cap.
They are willing to use their tool to remove them for me for $30.
My question is - has anyone done this job without the tool? I am
thinking that a pair of channel-locks or a vice grip pliers may work
since I don't care about the old cap.
If the tool is absolutely necessary, where can it be found for less $$?

                                                          Thanks,
                                                          Jeff Wozniak