Originally Posted by Ruby478
there was a person on here that put a custom manic mechanic sprocket adapter on the rear axle which mean you can still mount the motor in the box using a custom rear mount
That's a thought. 110cc is a lot of motor for a trike. Does that motor have an automatic clutch built in? If so, then you could go directly to the above mentioned sprocket adapter. If not, then you'd need some kind of jack shaft and clutch I would think.
Trikes are inherently less stable to ride than two wheelers, so you might want to think about a really good suspension front fork and gearing it for speeds under 30 mph. Also look to your brakes for good stopping power. You said the bike is heavy now and it will be even heavier with an engine, plus going faster. Go fast = stop fast.
I couldn't bring up the photo you posted so could't see the box. What about some kind of air scoop to direct air through the box while moving and have an "exhaust" or exit point to the rear for the scooped air to pass through. While stopped for any length of time you'd need to think about the electric fans... maybe and maybe not. You'd have to try things out to see if the engine was overheating.