172 mk2 with JB3 053 gearbox (r19 16s ph2)

[mumpy]

Hi all, I just found out my 172 mk2 has a JB3 053 gearbox, anyone seen this before? I compared the gear rations based on information I found online and it seems to match JC5 129 for all gears except the 5th.

I couldn't fit the Vibra Technics gearbox mount on this one though so need to think about that one.