don't know what kind of issues your having or "damaged" areas
but i do allot of repair work on mine

myself ...
i scratch up the aluminum surface so its gritty and then put on a thin layer of bondo
for "auto's" filling dents because its "
resin " based....just as it sets up,
i scratch it up, like i did the aluminum.... then you can fiber glass cloth and or fiber glass resin right to the bondo for a solid patch.
otherwise i use 20 year "good " silicone for all seams and cracks
always looking for an easier way tho .... of course
