Where can I find the chassis number on a Superbug?

same place a most bug under the back seat

Under the back seat you will see an oval plate on the centre hump that is the acess plate for the gear shift rod coupling. Just in front of the locking screw on the hump it will be stamped.
Not blatantly obvious but it WILL be there

or like all 70 on vws itll be stamped on the compliance plate along with the month and year of manufacture on the apron under the bonnet
altho there seem to be a few VWs getting around with these missing for some strange reason
my convertble is i think it was never reattacted when it was resprayed

-Joel