Changing model train wheels

I just recently purchased a Key 4-8-4 Northern brass engine .

When it arrived it had all steel wheels including the drive wheels. what I need is the instructions to change out the DRIVE Wheels to the one’s with the rubber insert that were in the box.
As with most second hand purchases they never have the instruction page.

Do you know anyone who has the instruction page so I may change the drive wheels out?

Thanking you in advance

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