Dude this guy doesn't know how to eat properly and your suggesting insulin? You give some seriously dangerous advice sometimes.So steroids got you 36 pounds over natural?
you'll need to learn and tune insulin as your main anabolic hormone.
you can gobble drinks full of simple carbs and sugars. No matter if it's sugary water, glucose+water or mass gainers.
Begin by doing that after workout.
(assuming you're not diabetic).
Do that for some 6 months before even considering insulin injections (which are medically proven to help underweight people).