Since both heifers (243 and 282) are daughters of Smokin Gun (a Winchester son), I think you should try to breed them to the bulls exactly as you have them in order:
1. +X-Ray 825
2. +Sting Ray 10/0
3. Arquitecto 920
4. Red Rhino
5. Winchester
These are all five outstanding bulls that are widely used around the world with excellent results. We do line breed cattle some times and get excellent results, but to be safe, it is good to breed the Passport line (Winchester and Smokin Gun) to X-Ray. It is a very strong and proven cross. Many bulls in the Red Brahman breed have family in common in their pedigrees. I think you know what you are doing! I am still looking at the beautiful advertisement that you did with 243 on the front of the Thai magazine! It is so wonderful.