Replace fuel Injector O-rings??

I just replaced my clogged up cat but I think I blew the exhaust monifold gasket. I put my borla header on about 25,000 ago so I know how to replace it but I was wondering what else besides a gasket I will need. I replaced the fuel injector O-rings and the quick disconnect rings also last time. Should I replace them again for sure or could I try using the ones from last time? Those things are just so expensive on a college budget... especially after replacing the cat.

Thanks :wave:

You shouldn't have to replace the o-rings unless they are leaking. O-rings will last quite a while (well over 25000).