sm block Camaro header question...

[iluv69s]

my headers have no collector flange and when I mount them to the motor, the collectors end right in the middle of the crossmember. I'd like to weld collector flanges so I can unbolt the headers from the exhaust. I am thinking I should shorten or lengthen the collector so the flange will not be right at the crossmember...
Is there any benefit to either way??

on other headers do the collectors end before the crossmember?? or after?? anyone gotta pic underneath thier small block camaro w/headers?

thanks again SYC