Serial Number Locations

Singer 4A chassis
The brass Name and Number plate identifies recommended lubricants, the Company, place of manufacture and the Car Number (eg A1579S). This is the number required for vehicle registration and must match the serial number stamped on the chassis.
Brass name plate for the Singer 4A

You should also find a stamped, oval aluminum disc which identifies the Body Number.

Singer 4A body plate

The Name and Number Plate can be found on the side of the bulkhead. The Body Number Tag will be found on the scuttle as noted below.

4A Engine
Numbers on the chassis include the Chassis (main side member before the bumper support bracket), Engine (on the offside of the flywheel housing), Gearbox (top face of flange adjoining the clutch housing) and Rear Axle (top of casing).