cheers that is some help,, does the flare on the tube sit level with the top of where its inserted or does it sit down in the hole if that makes sense?? would you say flare to full is about 82mm??
also if u have a sump off could you install one of them and fill the sump on level ground with a fluid of choice up to the full mark and measure from the gasket surface/top of the sump down to where the fluid is?? its the gap of air between the bottom of the block and where the fluid starts the would be extremely handy..
Don't over think it.
All you need is enough oil in the sump to keep the pickup covered. If you have a HE street pan then put 6 litres into it. Add a tiny bit more if you are changing a large filter at the same time instead of a Z160.
I assume your car is mostly street driven. If you are doing circuit work you likely need a better pan.