Just a thought as I've never check the play in the shaft with the guide tube off, with the guide tube on what's the play like as obviously if it's a taper bearing then it's going to move around like it is doing.
As far as the tool goes I'm sure if you get the corteco seal its supplied with the fitting guide can't remember off the top of my head I know when I did my Mondeo DMF & clutch I had to order crank seal that came with it and that was corteco
Other way of doing it is to use emery paper get rid of any lips on the crank end then put masking tape around the crank end so not to damage the crank seal and just tap it on but obviously don't be too aggressive.
As far as the tool goes I'm sure if you get the corteco seal its supplied with the fitting guide can't remember off the top of my head I know when I did my Mondeo DMF & clutch I had to order crank seal that came with it and that was corteco
Other way of doing it is to use emery paper get rid of any lips on the crank end then put masking tape around the crank end so not to damage the crank seal and just tap it on but obviously don't be too aggressive.