Hi: Phil

Your Very Welcome,

I worked with a lot of the R/C lander light systems and know them very well. I know how they can be hard to size sometimes.
Phil, If you are putting the ring in a jet, You might want to turn the lights out ward for max light effect. I am putting a 120mm set in my big F-14 tomcat and the lights will be turned out for max light in the daytime (due to : the jets fly futher away then a scale heli). you will have to play with the lights and see what works best for you.

Feel free to drop a reply any time,
Aways glad to help if i can.

wayne.