Can a 245/45/18 fit on the 18" 7.5 rim stock 2005 rim?

Can a stagger set up of this work on the stock 18's?:

front: 235/45/18
rear: 245/45/18

or

front: 235/40/18
rear: 235/45/18

Any issues I should be concerned with either?

you should get 245/40/18 and 245/45/18 if you want to go the non-stagger route.

According to Tire Rack, the minimum rim width for the 245/40-18 is 8". However, it shows the minimum rim width for the 245/45-18 is 7.5".

Not sure if 0.5" will make much of a difference... Personally, I'd just opt for 245/45-18 all around, if you have a sedan. (Which is what I assume you are talking about, since you are talking about 7.5" rims)

I was wondering about the same thing cuz there aren't many choices of the stock 235/45/18... I do find a lot of 245/45/18 tho

Well I agree with you guys but those are the the two choices I have since I already have access to 2 tires of each size. So out of the two options I mentioned which would be best case?

front: 235/45/18
rear: 245/45/18

or

front: 235/40/18
rear: 235/45/18

Yes the sedan.