Steering box seals have arrived, now have to have another go at cleaning up the underside of the ute before I try pulling the box out. I know it's going to leave a giant mess of oil once I undo the power steering hoses so I am procrastinating about that. Found this video on rejuvenating unpainted plastic bumpers, might give it a quick shot on an unobtrusive bit of the front bumper and see how it goes: https://www.youtube.com/watch?v=AGyMoheuH-Q