I think I had the Murray's aftermarket barberhauler (internal to front beam) system to which you refer, on an old 5.2.
Here's a decription.
System had two cleats, one on each end of front beam, mounted in front of a hole in the beam in which which was a "exit block". Asingle line ran though cleat, into exit block, through the beam and out the other exit block & cleat at other end. It was about 4-5' longer than beam. At each end of line, either a 2-3" ring, or a pulley with becket, grabbed the jibsheets. When you are on stbd tack, you pull the stbd side line, and cleat it. That pulls port side jib sheets out near the beam, instead of sheeting down/in on tramp.
When you tack, you have to first uncleat the barberhauler & release jib, change sides, pull in barberhauler on other side, then sheet in jib. Just two more things to screw up in a jibe.
I always thought it would be better to have one cleat that could pull both barberhauler lines outward at the same time, be set once at top of downwind leg, released at bottom, but I never rigged it tha way.