fiberglass crack repair

this crack is in the middle of the "side" . I have no slide. I ordered the "access port cover" yesterday from Overton's and am now leaning towards drilling the two tiny holes at each end of crack ( I read here that that is recommended so the crack won't spread) and stick on a length of eternabond tape over the crack to keep out moisture. is the eternabond as "permanent" as the 3M sealant would be? it would be more flat and easier to cover than the sealant. again it is made with Azdel so I am not concerned with moisture/delamination etc.
it has been sitting for 2 years so don't know what could have initiated this crack other than perhaps something thrown up by a commercial lawn mower, etc.

thanks
bumpy