It's late 61 so may have been registered new in 62 as a 62.
That was also the same time that fuel gauges started.
It could be either a fuel gauge added in by someone or its possible the last of those bodies still had the reverse tap mounts but they werent used, is there a plug in the hole?
The 50/50 taillights came in in June 1960. The fuel gauge (and deluxe towel rail bumpers) came in in late 1961. The bonnet pull was moved to the driver's side in June 1962, the same time the rear lights were enlarged to 3-segment.
The Standard didn't appear until August 1962, so I don't think it's one of those. Standards never had 2-segment tailllights or passenger side bonnet pull.
3789669 is a 1961 chassis number, but the numbers were assigned by Germany and stamped in Australia. The August 1961 change to 1962 model for Euro/US Beetles doesn't apply to Australian-made cars. As Joel said, it could have been made in Melbourne in late 1961, or early 1962 and sold as a 1962 model.
Australia had a mini-recession in 1961, and car sales slumped. VW's Aussie sales dropped by 38%, from 28,600 in 1960 to 17,800 in 1961, and the Clayton factory laid off 90 production line workers. Even if your VW was built in late 1961, chances are it sat in a wholesale yard or on a dealer lot for a few months before it was sold. Sales recovered in 1962, but only to 24,600.
Have a look at the wheel centres of all four wheels plus the spare. There is a mm-yy date stamp in between the wheel bolts.