'70 R/R Gearbox ID

Hi,
A friend has just bought a 70 R/R as a project.
The car is 'allegedly' numbers matching.
My question...how do we id the gearbox for 'numbers matching'
The car is a 383 and the box is a colom auto.
Cheers
Simon

Look for a raised pad on the passenger side of the belhousing. If it is original it should have the last 8 digits of the VIN stamped in it.

Many Thanks
Simon