The 5-pin connector can indeed be used for the # TL21RK magnetic tow lights, if it's active. You can use a circuit tester like # PTW2993 as a helper activates each taillight function to confirm the 5-pin connector works. I've linked to a video showing my buddy Jameson demonstrating how to use the tester in case you're not familiar with how they work. view full answer...
You could cut off the two inches that you need from the lower bend on the # LA-401BA but you would need to find a way to crimp the end of the pipes to hold onto the mounting bracket. The ends of the pipes are simply rolled outwards to prevent the bracket from falling off. Most likely your local hardware store will carry some sort of pipe end shaping tool for you to accomplish this. view full answer...