does this package come with everything i'll need to swap out the stock headers on my 87 gta with l98? or is there anything else i will have to buy in order for these to work and pass smog? also how difficult is it to install these with the 350? thank you.

http://www.jegs.com/i/Hooker/520/2055/10002/-1

 

for a single cat car its everything. install fairly easy depending on mechanical ability.

 

you may need new plug wires with 90 degree plugs. i did