My guess would be that the cushion retainer and the crossmember
are not consistently flat so they used the two large area flat
washers as standoffs, something like spanning a rocky river bed
with a bridge. Two bridge abutments work better than one big
flat bridge laying on the rocks.

Denny G

Last edited by Denny Graham; 03/01/2013 6:21 PM.

Denny G
Sandwich, IL