I stripped the head off my 260E's pan plug. Tried everthinhg to grab & twist. I even drilled a hole into the middle to use an extractor on it. Nothing worked. I had visions of cracking the oil pan. Finally (after buying a replacement), I took a small sharp chisel and hit the edge of the plug. Hit it tangentially in several different places. Hard to say it, but easy to do. One spot curled up quite a chip. The plug unscrewed abut a minimicromillimeter (technical talk) and then it was loose. It just came out very nicely and acted all innocent. What a *****.
Now I suck the oil ot through the dipstick tube.
Suckers
BTW, hot engine oil is nowhere near hot enough to soften that steel plug.