I will answer my own question as it may help someone else in the future.
1) remove the rear roller - This is supported on a long axle which has a bolt at both ends - try to remove the left bolt (looking from the back) and ease the axle to the right. This will allow the roller to drop sufficiently to slip the belt off the roller.
Be careful to not the positioning of the spacer and any washers that you remove at this stage.
2) Remove the Height adjustment handle - be careful as this assembly contains a spring and the trigger - so note how this all goes together as you remove it. This will allow you access to the drive pulley, attached to the engine.
3) Now you can remove the old belt - it is a bit of a squeeze past the drive pulley (at the engine end) but can be done with a boit of effort.
4) Install the new belt by slipping it past the drive pulley and pushing it up the channel toward the rear.
5) Re-install the height adjustment - with the spring and trigger and replace the 2 screws.
6) Slip the belt over the rear roller and past the pulley tensioner assembly ( as both parts of the belt need to be above the tensioner pulley.
7) Push the axle back through the roller and make sure you put back any spacers that were removed to remove the axle.
8) Tighten the bolts at both ends of the axle shaft - but do not overtighten.
9) Start the engine and test.
I hope this helps as I have spent several days trying to find these instructions, to no avail.
Robert Welsh
May 2008
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