Accidentally put power steering fluid in my tranny

you should get the fluid changed , you can drop the pan ( messy) or take it to a shop to have it done , if you can get the tranny line off the bottom of the radiator where it's sent to cool and get a hose on it the pump in the tranny will blow it out , make sure it's secured and in a container because it's high pressure and will blow all over the place (also messy), or send a hose down the fill tube and below the tranny into a pan get a siphon going this will take some time or if you have an old shop vac you can suck it out with that , I've heard even with the pro purging method you never get all of the fluid