Cut your harness and make up 2 separate short pig tails that will "push on" your new C&G stop light push on terminals. Original 1939 and 1940 stop light switch was part # 91A-13480.
Photo below shows how Harley brake light switch was adapted to harness by cutting harness and connecting Harley terminal that came with wires attached. This Harley switch uses spade connector terminals.
Harley brake light switches are also often used as they seem to be more resistant to DOT 5
brake fluid and operate on low pressure.
https://www.fordbarn.com/forum/showt...e+light+switch
https://www.lowbrowcustoms.com/colle...light-switches
Here's one that uses screws to attach terminal wires. Sadly, it's not made in USA.
https://www.amazon.com/Koauto-Hydrau...14711518&psc=1