This is a question outside of the airline and transport world, but I am trying to get some guidance on a situation (before getting a lawyer involved) to move forward with a business I am starting.

I have an STC which applies to Cessna 172 models F,I,K,L,M,N,P,Q,R, and S variants. In the Limitations and conditions there is a line that states "This STC is applicable only to Cessna 172 models with 150 HP engines, or greater, and STOL wingtips."

After doing some research, I have come to find out that there are no "STOL wingtips" that exist for the late model 172's (R & S). Aside from getting field approval for the deviation on a 172R, how should I approach this wingtip requirement of the STC when it is impossible to install the "STOL" wingtips on the R & S models?