Yeah, you gotta eat more dude. I know it's hard, but lots of things in life are much harder. I'd say over the next 18 months, try for about 80lbs of weight gain. That'll get you to 185. That averages out to about 4 lbs per month, or 1 lb per week - give or take a bit.
I know for mini-males that appetite is an issue, but you need to train yourself to eat more frequently and more per sitting, just like you train with the barbell.
Liquid Calories are key. You can easily make your own shakes that are 1000-1500 calories each or even buy them pre-made. Then benefit of the pre-made shakes is that they are convenient and there is less volume to drink. American Bodybuilding makes an XXL mass gain shake in a fairly small bottle that is 920 calories a pop. They are very smooth, thin, and taste ok. Easier to consume than a big blender full of stuff. Order a big giant shipment of those and drink 1 per day
Buy ABB Performance - Extreme XXL Mass Gainer Supplement Strawberry Banana - 22 oz. at LuckyVitamin.com