wheel struggles

[XAAMOTTOMAAX]

I finally found an 18" wheel that I like, but the moron over at the wheel shop is trying to tell me they dont have an application for my 9-5. They do have an application for the Caddilac Catera though which is the same 5x110mm bolt pattern. He says the problem is in the offset. But the wheel is an 18x7 with 20mm, 35mm, 38mm, and 45mm. I am pretty sure an 18x7 with a 5x110 bolt pattern and a 35mm OR a 38mm offset would fit fine. Could someone please just verify this so I can know for sure before I order them?
Thanks!

[mr saabman]

It's not only the offset you have to consider! the centre bore matters too,is the centre bore 65mm or can you buy an adapter if it's bigger? if smaller you will have to have the wheels machined to the correct center bore.
The offset for the original wheels is ET49 and you should keep to that if you can,I'm on ET35 17"s which are not ideal :(