hi I have the 2000 Nissan maxima with the 3.0 in it and I bought a a set of headers with the down pipe on ebay and I cant seem to get it to line up right the headers bolt right up to the motor I jus cant get the down pipe to line up the with headers now I don't know I if the headers and down pipe or the wrong ones or I'm not jus doing it right????

 

https://maxima.org/forums/5th-genera...r-install.html

 

Try loosening the header bolts on the manifold a little to give yourself some more wiggle room to line everything up if possible, then once you have it all semi put together, tighten everything down starting with the header bolts....that helped me line my headers up pretty easily, but I'm not so sure about the ones you have here, there may still be issues