As it says:

Quote
Tacoma TRD electric locker also uses an 8.0" ring gear and what appears to be the same electric locker as Toyota used in the 4Runner. It doesn't look like this electric locker will retrofit it into the 8.4" non-TRD Tacoma axle with an open differential unless you obtain the entire TRD axle along with the locker.


The e-locker (8") won't swap into a 8.4" Tacoma rear axle (non-TRD) or carrier. I think all the e-lockers will fit into any of the 8" axles (front or rear) with the proper mods.