There are no tables for ASD or AGD because there was no requirement for the OEM to produce or provide such data
ASD - an extremely conservative calculation .. but that's fine.
Accelerate go distances with a 1959 Piper Apache PA23-160 ? Probably not relevant to real life ... perhaps even a
non sequitur .. I did my initial twin with a very experienced TP (thanks Hugh) on the Apache .. for the OEI stuff, I flew the aircraft and he operated the "failed" engine sufficient to preclude our killing ourselves.
I suspect that your calculation would be non-conservative ..
Under both 6000lb and the traditional 70mph/61kt maximum stall speed a light twin is basically a single with half an engine on each wing ... see, for instance,
FARs 23.66 and
23.67.