ID plates don't mean much except you can't rule it out. The console and headlining are far better indicators. Are you sure it is GV4? Extremely rare option behind any 3.3L M20 HJ commercial. GV4 (3.36) wasn't even optional behind a 6cyl 4spd in a HJ passenger vehicle. The only place i'd expect to see it would be with L20 M40 driveline where GV4 was standard or possibly behind an M22 or M15 both which have a decent reverse gear.

Edit, I just went to record the car and I already have it but as an M40 trimatic, which explains the GV4 diff.