I have a Pelican Apex 130T that I cinched down too hard on my roof rack. It pushed in the bottom underneath the backseat and deformed it. How do I get it back out and get a normal looking bottom of this watercraft?

This can be difficult. If it was my boat I would try:

1. If bottom flat, lay on flat floor like garage or deck. If not flat, then work on lawn.
   
2. Let the sun (and maybe a bit of extra heat, but not much) warm the bottom so it is a bit pliable.
   
3. Apply force to put the bottom back into shape. If not a flat bottom, then some care is required. This is usually done with internal blocks of wood or foam to hold the hull in its proper shape. In more extreme cases you can inflate an air bag in there to maintain pressure over a larger area. (BE VERY CAREFUL if you use an inner tube--it can burst your boat!)
4. Once it is back to about the shape you want, leave it in that position for a few days, and to cool down.
   
5. With any luck, that will reverse most of the dent. If you don't get it all the first time, you might want to try again. In fact, I suppose it might be better to work on it twice rather than do too much in one go. I really am not sure on that part.
6. With these poly boats, you may never get them back to original shape, but they will almost always accept some re-bending to get back to a more useable shape.