I see you put new DOT tape alongst the edges-good idea. More visibility is best!
Now-looking at ur trailer closer--might be a small problem n the installation, but a man of your knowledge/expertise--shouldn't be a bigee...The top "rail' of your trailer looks round-like pipe. The two side pieces for the Gorilla lift are square tubes-2" , I think. Might have to figure out a way for the attachment bolts (they are supplied)- to fit to the top of the side rails on ur trailer. There has to be enough space inside the square tubes for the two springs/windup cable to fit, and to extend and retract--thereby raising and lowering the rear gate. Now that I think about it--there are instructions in the box--it might explain how to work around this issue. When I installed mine--it bolts right on -four holes to drill....but I installed the first side on the opposite/wrong side--and the cable wouldn't retract. That was a head scratcher for five minutes...DUH...
I'm sure you'll figure it out--post pictures afterwards......and good luck....Oh--On the back tailgate, at least on moine--there is two round rods at the bottom of the gate, that attaches it to the trailer and it pivots on--mine was 'squeaky' -it's galvanized. I took them out-applied a thin layer of 'never seize' --much better and smoother now.
Take care, my friend!