So this is correct (assuming you earn basically up to $180,000...

So this is correct (assuming you earn basically up to $180,000 the tax will be 37c for every dollar you make, every dollar AFTER the $180,000 will be taxed at 45c in the dollar.

The CGT (capital gains tax) discount applies after holding for 1 year. The CGT discount is 50%, so whatever tax bracket you end up in (assuming 37c or 37%) will be halved.

37 ÷ 2 = 18.5% tax
This also includes your INCOME or SALARY, so be aware that if you make $180,000 plus, what you make on shares will have a different tax rate (45c instead of 37c).
There are a lot of other factors including tax free thresholds. For example last years tax return, I was nudged into the top bracket from capital gains and panicked thinking I would now be taxed at the top rate for ALL of my income I had received throughout the year (not just the capital gains) but thankfully I only had to pay the top rate for every dollar OVER the $180,000 (My concern was I would have to pay an extra 8% tax on my income I'd only paid at 37c and not 45c).

ALWAYS, keep the money for tax aside separately and overcompensate a little to be safe from the tax man.

And as always this is not financial advice and correct to the best of my knowledge. DYOR