Harvey,
Have to take issue with this post of yours...
"This is the way it should be assembled:
591985
571933
593617
591478
REMOTE
With them all stacked up like that. "
The parts book diagram is very misleading on this.
When dismantled nine had
593617 direct on the remote, then
591478, then
571933 then
591985.
The reason this works for me is that both of the first 2 items have cut outs for the locating part of 571933. If it is done your way, why is there a cut out in 591478? The other way the bottom of 571933 is neatly flush with the bottom of 593617 and both locating cut outs are engaged.
??
thanks