Stumbled across this site not long ago and Ive got to say its full of great information. I went from a 98 Tacoma access cab 2.4L 2wd to a 07 4x4 Double Cab Short Bed 4.0L 6 Speed Manual.
Came to this site looking for some information about towing (my truck did not come with the tow package, which im kicking myself for now) and ran across information about the Rear Spring TSB which had done this weekend!
Here's a pic from when I got her back in march of last year. I'll put some new pictures of post-TSB soon. It raised the back end up around 1.75 inches.
this is still when it was brand new. Pre-TSB