What is a good "rule-of-thumb" when trying to figure what the allowable change in offset is for Mercedes?

If the car runs a stock et37, can one go in or out off of centerline what amount?

i.e.- (W140) 8x16 et54, but you can use a et47.

Any help?

TIA

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1994 E500 (MY SUNDAY DRIVER)
1993 190E SPORTLINE LE W/ M104 SWAP
1997 C230
2002 ML320
2000 BMW 528I (WIFEY'S CAR)

"Excuses are crutches for the unfounded."