The wheels themselves are 245/45/20 the rims are 20X8.5 5x120
Tyres are tyres, rims are rims and when they are mated together they become wheels or rims and tyres.
That helps when asking questions.
As pointed out the 45 profile tyre size is wrong and 35 profile tyres are common and readily available and can be sourced same day or overnight by retailers if not in stock.
A 245/35/20 has an overall diameter of about 680mm
A 245/45/20 has an overall diameter of about 729mm
A difference of 49mm or 7.2% which is way too much.
20x8.5 is the rim diameter and width.
5x120 is the PCD which is the measurement for the stud pattern and in this case it's a Holden Commodore stud pattern but is also common to BMW's and can be for some other makes.
You will need the rim offset measurement to determine if it rubs or not but in most cases a 8.5 inch wide Holden specific rim shouldn't rub unless the retailer has absolutely no idea.
I think for memory Holden uses a positive +48 offset for an 8.5 inch rim and that's conservative to avoid rubbing and suspension problems.
If in doubt any reputable retailer will check fitment on the vehicle before you buy in case you're not happy or they don't fit.
Also google how to check the date of manufacture on the tyres and if they are old stock, walk away.
It's generally accepted that after 6 years regardless of the condition of the tyre it has run it's life and no longer will preform as it should.
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