You know, I've looked several times for a map that shows all the rest rooms in the parks, but have never been able to find one.
If you are just looking for any kind of restroom, all the park maps have all thre restroom locations marked, with the exception of the restrooms that are inside restaurants.
You can also go to post 3 of the disABILITIES FAQs thread, located near the top of this board or follow the link in my signature.
There is a link there to a website someone made with pictures of all restrooms at WDW. Thy even included some in restaurants.
I have seen maps with all rest rooms marked. I can't seem to remember right this instant, but I will try to find them for you. This is invaluable information, and necessary for your circumstance.
I wonder if I'm thinking of the Guidemaps for People with Disabilities.
I promise I'll keep looking.
If you are looking or the Companion Restrooms, they are not marked on the regular maps, but are marked with an icon on the maps for guests with disabilities. Post 3 of the disABILITIES FAQs thread also has a link to a thread I made called Restrooms around the world. That thread lists the locations of Companion Restrooms and has pictures of many of them.
Toy Story Mania does get backed up sometimes waiting for the accessible car. At IASW they can board any boat, when I was there that line moved super quick at the alternate entrance except for the one party waiting for the accessible boat (I actually was in the regular line for that one since it looked short, not realizing that they would continually board anyone coming in from the alternate entrance into the 2nd boat immediately and there was a steady stream of folks walking on down the alternate entrance with no
scooter or wheelchair).
Nothing's perfect, in some cases it will be a help and in others it will be best to get a fast pass or possibly skip it.
We have to use the accessible boat at Small World and have had long waits there. Until the person who needs the accessible boat gets to the bottom of the boarding ramp, we have never seen them pull out anyone from the line waiting to board ahead of us.
Once we get to the bottom, they will ave us wait to the side while they take people ahead of us who don't need the accessible boat. But, if you are in a long line, the wait can still be long.
On our last trip, my DH got into the accessible line with DD in her wheelchair while I was doing something she could not do. By the time I caught up to them, they had been in line for more than 20 minutes and were about 2/3 of the way down the ramp.
I looked at the line to see if I could catch up with them, but it would have been hard. Even though the lines look very wide, when there are wheelchairs and
ECVs to get past, it is not easy and/or always quick. People in lines can move out of the way to let other guests pass by; wheelchairs and ECVs often can't move enough to let someone by very easily.
Because I could not get to them, I got in the regular line. The posted wait time at that point was 20 minutes. I got boarded into a boat a little less than 15 minutes.
DH and DD were 3 boats ahead of me and DH told me later that they were lucky and the wheelchair boat came almost right away after they got to the bottom of the ramp (because of the regular line going behind the clock, I could not see them the entire time).
So, they waited more than 20 minutes more in the accessible line than I did in the regular line.
So, there is no way of knowing what your wait will be in the accessible line.
I would go with a touring plan or smart phone app that lets you know what the busiest places are so you can avoid them, use Fastpasses and know where the bathrooms are.