Starter shim size?

[DJV]

I'm putting a new starter into a 84 Iron duke.
The starter I pull out was not original and it had a shim with it.
I have an AC Delco that I'm putting into it and it did not come with any shims.
Do I need any with this new starter?

 

[melsg5]

You can either measure the tooth gap between the ring gear and the starter pinion gear, a paper clip should be able to fit in the tooth gap, or install without a shim and listen for noise and then add the shim or just reuse the shim.