My engine hatch had a loose screw on the strut bracket that mounts to the engine hatch. I went to torque the screw, it wouldnt move, so I tried to unscrew it. Then with hardly any force it broke the head off the screw. Now the stud remains in the hatch. I drilled it, then used an EZ out to try and remove it, and it broke again!

These are machine thread screws, so is there a nut plate or some other type of fastener inside the hatch? My local marina said to simply relocate the bracket just over from its old position, or remove the vinyl covering and find out what is inside there. I really dont want to do that. Im afraid that if I use standard wood screws, they will just strip out after a short time. Im thinking whatever that old screw was fastened into, is spinning inside the hatch, and I cant get ahold of it. Any ideas on how to fix this problem?