1/2 inch you have opetions. Dicor caulk (the non self leveling kind)
Or eternabond.. You could take a 11x11 inch square from Camping world
Cut in quarters (5.5x5.5 inches)
Prep the surface (Clean very well as per instructions)
Slap the patch on... CAREFULLY (It is not called eternabond for nothing)
Roll out and done.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times