GE dual voltage 3 phase motor missing wiring diagram

I purchased an Axelson lathe with a 15HP GE motor. I was told by the prior owner it was a 440 only motor. The motor nameplate was originally stamped 220/440, but the 220 is peened unreadable on the plate (intentionally). I have been temporarily running the lathe piggybacked off another lathes step-up transformer to get the 440 from my 220 power. I need to use both lathes simultaneously next week so today I bought a second 220-440 transformer and started installing it. I was going to redo all the wiring as this would be the way the lathe would be permanently wired. When I removed the cover off the motor's connection box I was surprised to find 9 numbered wires! However, the connection diagram is missing.

How can I verify my hunch that this motor is a 220/440 dual voltage motor? Anyone know which wires to connect for 220 volt use?

The motor's nameplate info is:

General Electric Tri-Clad Induction Motor
15HP
Model # 5K326XA90A

You can certainly try the standard low-voltage wiring:

1-7
2-8
3-9
4-5-6

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