Hey Karljeff72, I have to agree with Aggieman. I think you’ll get some bleeding with the template. I tried the template method several times, but I had difficulty with bleed through and keeping the demarcation lines parallel. If you’re interested in how I do my spinners, I posted a quick how-to back in 2017. (Check out my response to Chemteacher’s post regarding the same exact issue. My reply is #9.) The only only change I’ve made to my process since then is I’ll sometimes use very thin strips of Tamiya tape instead of electrical tape.
Hope this helps and good luck!
-O