Question on Boxster Wheels

I own a 2001 Boxster S. I want to replace my existing factory 18 inch wheels, with four aftermarket Motegi mr 122 wheels.
I want to go 18 inches with the new wheels, because my tires are new. I also want all the offset spacing to be like stock.
What are the factory offset spacings?
What are the stock wheel widths front and rear?
Depending on which site I looked at, some sites said certain sizes of wheels fit my car, while other said they did not. The same size was entered.
I am very confused.

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This post was auto-generated based upon a question asked on our tech article page here:

[Nick at Pelican Parts]

The factory wheel options were:



- Nick