OBM - Bridge Deck Template - Is it possible to have 2 working points?

Is it possible to have 2 working points for a bridge deck? The distance from the left edge of deck to WP1 would be 10 feet constant. The distance from the right edge of deck to WP2 would be 10 feet constant. The distance between WP1 and WP2 would vary so the overall deck width would vary. Thanks, Eric...ver. 08.11.09.211