The wheels are Bontrager Rhythm Elite off a 2009 Trek Rumblefish Elite.

There was no thread on the axle, nothing to fit a spanner too, it just pulled apart by twisting of off.

I got the freewheel and drive side end of the hub off, but there is no obvious way to pull the other end through. I even whacked it with a mallet (not hard enough maybe?)

There are cartridge bearings in freewheel.

I have no idea where the play is coming from, and whether it actually matters. I can't get the cartridge bearings out of the wheel as I can't get the axle out. Anyway, I cleaned it up, re-greased it and put it back together without having any parts left over. Still has lots of play though.
Anyone got any advice?
Thanks for your interest.

Simon