He has some 1204 ballscrews on his site http://cgi.ebay.co.uk/3-anti-backlas...3A4%7C294%3A30
Not sure if you could fit them as they have a mounting plate. I had enough problems getting the ones I got from Marchant Dice and they did not have the flange although they also do not have provision for wipers.
As I only have the X1 I am converting I also had to buy a spare y axis unit so I could machine it to take the ball nut. I got it to fit with 0.5 mm clearance, the other axis are quite easy as there is plenty of room for these.
I am now looking into moving the y-axis motor to the rear of the machine as I have ended up with a large overhang(could diet I suppose).
I am also looking at the possibility of raising the complete z-axis to allow a plate to cover the y-axis when in the fully forward position, I dont like the thought of all those chips on the ways and ballscrew.
Other problem is lubrication of the ways as there is no provsion at the moment.

Peter