I've been fitting electric power steering to the Avenger over the last few weeks. The steering at parking speeds is ridiculously heavy with the quick rack and smaller diameter steering wheel, plus the wider tyres.
I got hold of an EPS column from a Corsa B
Once stripped down it looks like this. The steering wheel spline is the same as the early Avenger. Unfortunately though, the shaft is too short so needs modifying anyway.
By far the most difficult part of fitting this motor into the Avenger column is deciding how far along the column it should sit. Space is really tight in the footwell/pedal box area and some time consuming trial and error was required.
It's necessary to remove a semi circular area of the pedal box to give clearance to the motor, otherwise it's impossible to lift the column high enough in the car. I took this cutout right back to the captive nuts for the stop light switch bracket.
I actually had to remove a little more after this photo was taken, literally right upto the captive nut.
The Avenger/Sunbeam steering shaft is 769mm long, so the new column total length needs to be the same.
The Corsa UJ can be split with a mallet easily. It has a DD (double D) connection. The lower part of the Avenger steering shaft was cut to length and then ground into a DD shape at one end so it's a tight fit into the UJ.
I then made an outer piece by joining the original Corsa flange with some 2.25" exhaust pipe. I sleeved it down at the bottom end for a 3/4" ID/2" OD sealed bearing, and welded in a smaller section of pipe to act as a bearing stop. The end was then peened over in a couple of places to retain the bearing. The plate that bolts to the floor needs tacking on when the column is fitted in the car, as it doesn't sit perpendicular on the pipe.
The hole in the floor is already big enough for this pipe to fit through.