I would use heavy floral wire. It’s thin, strong and stable, and will help your numbers stand straight and firm. Any floral shop will carry the wire. I buy mine there for my gumpaste flowers. Most florists are accommodating in selling it. I wrap the end of the wire that’s going into the cake in plastic wrap. Bare wire should never go into a cake.
Hope this helps.
Creativity is God's gift to us. Using our creativity is our gift back to God. Clarky's Cakes 😎
