Way, way overdue but I am in the process of completely lofting the later set of lines for rebuilding A146 (as in new hull and deck, have big pile of Agba veneer in shop downstairs). One thing to note is that I believe the hull lines are lofted to the inner skin.
Am kicking myself as way back in 1985 when got A146 had a pretty complete set of full size drawings but they went walkabout.
I am lofting the hull in Aerohydro Multisurf.
I imagine they added the volume aft to correct a trim problem.
Will have to compare but are the offsets you have drawing A 24522? I have the same problem as you reading the offset table. Actually have worked with a drawing printed out at as best I can tell correct scale and working off the lines themselves but having issues with getting the exact dimensions.
The forward half of the boat should be the same. Our boat is a 1961 build as best I can tell so definitely the later lines but plan on going inside at a couple of known points and confirming.