one last question about play in the wheel

I just changed my gearbox because I thought it was bad. after having to ask how to do half the work (thanks guys) the wheel still has just as much play in it, my question is what else could be causing all this play? the column connects to the gearbox tight and I can't see any play there...please help because I have just waisted alot of time changing this dang gearbox for no reason... lol