Trim Intermittently Working/Battery Drains

I have a 1993 Stingray with a MerCruiser 4.3LX/V6 Alpha One motor. "Trim up" button does not do anything or make any noise. "Trim down" clicks/knocks by the trim motor and then works most of the time and "Trailer up" works all the time. The Paul Harvey version ... Last year when I got it out of storage I hooked up the battery backward. It was dark to my defense and the length of the wires matched perfectly. I didn't know it until i smelled electrical smoke in back of engine. It worked somewhat last year ... I used the trim down button and trailer up button to trim up ... but now it drains my battery in couple hours.

I am not an experience boater but don't mind getting hands dirty. It also been nearly impossible to find anyone to work on it.

My initial thoughts is that it's the trim buttons. Since it will trailer up, i was thinking relays/pumps working fine. But I smelled smoke from the back of engine last year.

I did attempt to check for any melted wiring in back ... but didn't see any.

Any suggestions where to start?

Something to add ... trim up button every now and then will hear a click/knock like it's trying to engage the pump in rear of boat.

Trim has three control wires coming from helm going to trim solenoids. Red/white, green/white, blue/white. The red supplies 12V to the solenoids and the green and blue are the uppy-downy control wires. There is a larger supply wire going to the trim motor that runs it. This passes to the solenoids and depending on whether you want up or down will run the trim motor forward or backward. Given that it runs at all means that at least one of those solenoids is doing its thing. The problem is likely that the solenoid that runs the motor in the down direction is either cooked or a wire got smoked. That would explain the clicking.
You can mess around trying to repair it but I would replace the solenoids and wiring just to be certain. Worst case scenario is that you buy a complete good used trim pump assembly on eBay.