Firstly, you should not have seperated the drive shafts that way. The bit on the end is the inner member of the inboard pot joint, and you can now never reassemble it exactly as it was, with the balls in their original slots. You must never, ever mix balls from one pot to another as the size varies slightly to take up manufacturing tolerances, and the actual joints themselves were made by at least two companies to different internal dimensions.
Before you do anything else, get a Haynes manual, and read it, several times.
As you may now need new pot joints too, you can just knock them off, with a couple of hard blows from a brass faced hammer, but save the balls, each with its own inner member, just in case they are fit for re-use. The balls will fly out if you try hammering. The pot joints are also going to need new rubber boots, as I can only see one tattered remnant.
The official way of doing it is to extract the shaft from the pot joint, leaving the complete pot joint in the diff, using a Rover tool, shown in Haynes. You then put the shaft in the vice, and with the boot removed, apply a hard impact with the brass hammer to the inner member of the CV to remove it.
If you do it the official way you don't have the impossible problem of threading the complete shaft through a hole in the subframe, or putting the pot joints together in filthy conditions (dirt will ruin them quickly) under the car.
Without the tool for extracting the shafts from the pots, a viable alternative (too late now in your case) is to remove the hub, leaving the shaft in the car, and while holding the shaft into the pot, pushing it in towards the diff, whack the CV with the hammer to get it off.