When I was doing rescues I figured out a way that worked for me. It involves doing a consistent routine of holding him in your lap twice a day, and making him stay there by holding onto him with both hands. You give him tastes of "freedom" by loosening your grip a little. When he tries to lunge away, you retighten your grip. After as few as a dozen to as many as a hundred repetitions, he won't try to lunge anymore. He is rewarded by being free of your restraining grip. During this training, you start to hold bits of treats on the end of a short stick under his nose. If you're lucky, he will passionately like some of them, which lets him associate being with you with yummy experiences. Banana, pizza crust, half grapes, and more. By now he likes you, or has stopped loathing you, because of the positive experiences he associates with you. When he can sit unrestrained on your lap, you can let him wait there until he gets the idea to crawl off and explore. When you pick him up again, learn how to make the chase very short.
You can't predict how tame he can become by how vicious he is now. I've had really awful iguanas become real sweethearts. The theory is, all iguanas of over four months old can be tamed, but that might not be absolutely true.
There are some good tips, such as always warming your hands before handling him. If you want I can expound more on this.
Don't make it a requirement that he submit to you when you put your arms in his cage. Just learn to grab him quickly, then press him belly-first into your mid-section until he stops struggling. IMO for all iguanas, this initial struggle lasts for 30 seconds. When he stops, relax your grip so he can breathe, then take him to a comfortable place for you to sit.
You can get cheap, woven Kevlar gloves for protection. Also get Kevlar "sleeves" with thumb-holes. Put them on over the gloves and you're fairly well protected from scratches and bites. Wear a denim shirt and pants to protect your skin from his toenails.
Make the routine exactly the same each time so he is never surprised by anything new.
There are more details to write about if you want them.