Upgraded Mitsubishi LT-5V.Arms effective mass?

Out of parts of two original tables and some intensive cnc
metalwork i have made my dreamturntable.On it is the V.D.H.
Frog cartridge(with fine results).I want to upgrade to the Condor V.D.H but before i do i need to know the arms eff. mass which i can't
find in the instruction book.This is a parallel tracking arm.Does anybody know this detail or knows of a way to measure it?