I am hoping some of you "Model A" experts can shed some light on a very confussing issue I am dealing with on the dimensions for the rear buggy spring on my Model A. My spring purchases are mounted at 49 1/2" eye to eye. The spring, at rest, unmounted, measures 44". In researching available Model A springs the dimensions of the spring at rest is 39 1/2" . My question is, are there two different springs used on a Model A or has my spring stretched to 44"? If 39 1/2" is the correct dimension, does that spring stretch to mount to purchases spaced to 49 1/2". Any hely will be greatly appreciated.