Traditionally, when you close a bracket at the end of a sentence, the full stop is placed inside the bracket - ie .)

I'm wondering if it's acceptable to put the full stop outside the bracket nowadays - ie ).

Any thoughts would be most appreciated!

It all depends.... (Sorry!)

This explains quite well

http://universitywriting.shu.ac.uk/punct/advice/s_brack.htm

I was taught in ' correct ' use of English writing that the full stop is inside the closing bracket.

Rebbonk's link seems to say that any punctuation belonging to the sentence inside the brackets belongs inside them too, while any punctuation belonging to the main sentence stays outside the brackets.
Am I reading this correctly?

That's my interpretation. I particularly like the examples provided.

I often find university sites useful for things like this. The Times Style Guide is also quite useful. - I bought a copy many years ago. Whilst it isn't infallible it does generally point you in the right direction.