Given the dearth of 3 Rail Atlas O Front Runner & 45' Pines Trailers I embarked on a project to convert the 2 RL version to a 3RL version and they turn our pretty nice. The key is to change the truck AND the coupler shank. I used the 3RL 100-Ton Roller Trucks (#66030) to replace the trucks. The coupler ends up under the car and it will not negotiate a turn of any radius when multiple converted Front Runner cars are connected and will barely negotiate a O60 turn when connected to a standard 3RL car. I then installed the 3RL Medium Coupler Shank (#66042) which resolved the issue. The photos below show the issue when installed. Bottom is the 2RL, middle is the 3RL with stock 100-Ton Trucks and shank and the top is the 100-Ton trucks with the medium shank installed. The next photo shows the length difference between the stock 100-ton coupler shank and the medium coupler shank. The next two photos show the car on the rails with the stock shank and with the medium shank. I hope this saves someone else some time.