Its an odd Ball Aussie Borg Warner Flywheel. Its originality a Hemi 6 re-ballanced in Oz to Mopar Spec for the 360. US 360 Flywheels dont fit.
Converted Surface Ground and Balanced Flywheel [Small Block 360]
So yes, it was a bit naughty of me to run it behind the 340 but I knew it was not for long as the 340 was needing pulled and rebuild anyway.