I haven't messes with Baja forks but I have replaced springs (aftermarket upgrade) and seals on motorcycle forks without completely disassembling them. Don't know about the Baja fork, but on female-slider motorcycle forks, the spring comes out the top end of the tube when the cap is removed. You should be able to replace the seals without separating the slider from the tube.
Dump the oil.
Clean the tube.
Slide the wiper/dust seal up and off of the tube.
Oil the tube at the seal to help prevent scratching it. Use a seal puller (Of all things!) to remove the seal, being careful not to scratch the tube. A seal puller will set you back around ten bucks.
Clean and oil the tube to prevent damaging the new seal.
Slide the new seal on and gently tap it into place; a properly sized PVC pipe would drive it in evenly, but working your way around with a soft-faced hammer will work, just be careful not to bend the seal. You may need to use something (I suggest a piece of nylon or hardwood) as a punch to fully seat the seal, depending on how deeply the seal seats.
Replace the wiper/dust seal.
Replace the oil. The volume varies with the particular fork, obviously. Specs are available for motorcycles but finding them for a Baja would probably be a challenge. Too little oil will result in little or no damping; too much oil will result in reduced travel and/or blowing the seals out. I have always used actual fork oil but people have used ATF and motor oil. Higher viscosity will provide increased damping. The best cure for bottoming would be higher compression rate springs. You could insert an oil resistant rubber rod inside the spring; start with full length, shorten if it's too stiff. You could insert a smaller compression spring inside the existing one; it would need to be wound in the opposite direction to prevent binding.
https://www.mcmaster.com/#standard-rubber-bars/=1dsc5rz
The bolt on the bottom probably has an o-ring seal; there's a possibility that all of that spinning the bolt you have done has damaged the o-ring and it may now leak. If it leaks and you still can't remove it, you could clean it and the surrounding area with solvent and pack some epoxy around it; KBS Coatings epoxy putty is the best I've ever used.