dumb question but are all 4 of the 02 sensors the same?

 

im not sure, but i really dont think so. i dont even think the rears are heated.

 

As far as I remember, all the ls1 o2 are the same type except the length. I remember reading about certain corvette ls1 o2's are even cheaper than the Fbods, and guys use those to save a few bucks. do some google searches to get the pn's.