Passing emissions...need some advice

[Seanzyyy]

ok,i have a 1997 240sx se.obd2 sucks =/

well, i have 4 codes..second o2 sensor, knock sensor, and 2 evap codes.

here's what i think i need to do:1) replace the 02 sensor (the current one froze when trying to remove it)2) weld the exhaust (it cracked in half on the pipe right after the second cat)

3)reset codes, then re-check to see if the o2 code is gone, if not, i guess i gotta change my front cat.

4)i've read and heard that the knock sensor code may go away when i fix my o2 sensor and/or evap.so i'll prolly tackle the evap first, maybe replace the whole shibang lol

5)rest codes, then check if evap codes are gone.

6)if knock sensor code is still up, replace, reset, and check.

i was wondering...in tucson, do i need 2 cats? would i be able to remove the front one?

how much do you think this will all run me? i plan doing it myself..i have the o2 sensor, i know a knock sensor at autozone is like 130 but i can find one online for like 30..i can get the front cat for maybe around 80?how much is an evap canister? and anything else i need?

thanks for any help