rear spring help (deaver F55)

ill try to make this as short as possible. feel free to skip the first paragraph.

i have a 2010 double cab 6 speed trd off road 4x. rear springs are saggin hard. the truck has bilstien 5100s all the way around (i believe) and they are maxed out. the truck rides ok in the front and like shit in the back. bottoms out on everything. i am having trouble with the recall as i have 2" spacers in the back to level the truck out and no dealership seems to want to touch it unless i put the entire truck at stock height (which would require lowering all of the shocks and then having 285/75/16 tires that wont clear for shit) just to have the recall done for another set of shitty springs with my current spacer.


there is someone selling a set of used f55 deaver long travel springs for 300$. but he says they came off of a 2000 tacoma. the deaver site shows the same part number whether i search the 1st gen or 2nd gen.
on to the questions
1 how can i find out if they fit my truck?
2 is 300$ a good deal on a set of used springs?
3 what is the guess on the ride height after install and would i be able block it or what would i need to do in order to make it ride close to level (or ass end up an inch. anything but lower in the rear)
4 assuming i get this far, what all is involved in a long travel spring? is it just a bolt up? or do i need to start thinking about other things like driveline or god only knows what (i am clueless sorry. any help would be appreciated here)
5 can i just use plasti dip to fix my current springs? (sorry but a post doesnt seem to be a good post on here unless plasti dip is involved in some way)

thanks in advance (as i wont be thanking you later. you got your thanks. now give up the info sluts)

 

get something that is meant for your truck. Buy once new and cry once.

 

well no shit!! my first question was
"1 how can i find out if they fit my truck?"