Bent oil return tube on a six , is that bad,

If the tube or o-ring leaks then you will have to replace it. If it doesn't leak, leave it alone. The only bad thing with the 911 engine is if you want to use the factory (fixed type) tubes , you will need to remove the cam housings. Another choice is to buy the aluminum Expandable Oil Return Tubes which do not require the removal of the housings. They are not cheap at $50 each new. The nice thing is you can replace them all with the engine in the car and within about 1 hour. I've replaced a few with the expandable type, some are easy and some are a real pain to install.
Make yourself up a jacking/motor plate to install the engine. That way it will cradle the engine in a wider area during install and removal.

Agree, if it doesnt leak leave it alone