fan oven element repair

[Robbox]

The screws holding the element are f@*ked, tried WD40, but they were so rusted over the cross head became rounded off.
What should I do? Drill out carefully with small bit? It's too enclosed to cut a slot in the top and I don't have a Dremel.

 

[PrenticeBoyofDerry]

Screw removal tool or a pair of pliers/grips.

 

[Robbox]

have to be removal tool as they are impossible to grip

 

[Robbox]

I've just seen the kits on Screwfix. The element secured with no 6 screws. I hope the smallest will work. Do I also need a tap wrench? I don't see them as an item on SF.

Screw removal tool or a pair of pliers/grips.

 

[PrenticeBoyofDerry]

Which removal tool have seen?
The extractor bits, will require a screwdriver (You will also need to pilot a hole in the screw head), the nut removal tool will need a ratchet.

 

[Robbox]

I bought a set from screwfix, awful quality. Tried a test screw, but the extractor was made of putty!
Looking around, I've found one by Dormer, seems better quality.
I have a set of cobalt drill bits, they work fine. Used my cordless on slow to make the pilot, then again in reverse with the screw extractor bit.