First, if you have a Cap with a 1 piece wing it's not a Wild Hare Cap, so you're in the wrong place.

But if I knew more about the plane I might be able to help.

In general you want the prop to be centered on the cowl so it looks right. If the firewall has right thrust built in (as WH planes do) then you need to adjust engine location to the left side of the plane to make the front end of the engine be in the center.

If the firewall has no offset then you will need to add some by shimming the left side of the engine, and again moving the engine to the left so the front is centered.

I can't supply more detail than that for something I know nothing about.

TF