I ended up removing the entire assembly, sliding it off using stands. Though it was risky.
The thing must have weighed in at 80-90kgs.
Once on the ground, removed the Winch. Hammered and ground the crap out of the bumper to get the rust off.
Recoated with Hammerite and finish sprayed it twice.
Getting it back on was difficult but not as hard as I thought.
Looks good now!
Though this was almost 1.5 years ago.