I swear along time ago I saw an L with a system to adjust cylinder height with a small crank on the lefthand side . It was with the older adjustable system that had the bearing mounts that slid up and down with a threaded bolt . Not the newer style that pivoted from the rearward bolt . This system had a roller chain that went across the top of the throat and tied the adjusting bolts together If my memory serves me rite the chain was in a small cavity that ran thru the head . Does anyone else remember this ?