a pair of {HEAD ~ handhold means} having axes of rotation parallel to each other, each handhold means comprising an upper end pivotally mounted and detachably re positionable at a plurality of selected locations along {TAIL ~ the length} of the guide means; and 
a pair of { HEAD ~ handhold means } having axes of rotation parallel to each other , each handhold means comprising an upper end pivotally mounted and detachably re positionable at a plurality of selected locations along { TAIL ~ the length } of the guide means ; and
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH