Jesus, you were served one big-ass shit sandwich there.
So, as others said, dump the tank first. I would give it a good rinse-out with clean gas. I don't know if anything can/should be done about the nasty fuel now sitting in the lines and injectors. The other guys may have comments on that. Also tagging @superhawk996 for this.
Changing the oil is good, yet honestly, probably not super-critical to do it before a startup. Unless someone knows otherwise for sure, I would really hesitate to mess with the WD in the cylinders. I can see that doing more harm than good.