I had the same problem.  Finally found a very narrow ring compressor that I
could slide over the jugs after the pistons were inside.  Had to use small
wires with hooks bent in the end to help get the compressor over the jugs
and pulled out.  Small wires were made from electric fence wire.  Larger
ones were made of coat hangers.  It was quite an exercise in frustration,
but finally worked!

Let me know if you can't find a compressor and I will loan you mine.
Please reply to me directly as I sometimes fail to read all of the messages
in the list.

George