Hello Olaf,Hello and welcome here.
Crown Prince Wilhelm was placed on June 6, 1905 a la suite of the Seebattalion. I think at that time he was a lieutenant colonel or a colonel.
I think that he surely wore the epaulettes on his uniform
or shoulder straps depending on the event
I think that you can find a proper pair to dispaly with the unifrom
He did not obtain his higher ranks until later on
I have one of his brother's uniforms for Prussian Grenadier Regt 4
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