well i would say that it would have been alitle easier puting them in before the engine but its still doable with the engine in place, first put car on tall jackstands dont work under the car standing on just the floorjack thats a disaster waiting to happen, unbolt the steering centerlink from everything on the drivers side and slide it over to the passanger side so its out of the way, unconect your battery.
i think the passangerside header will just slide right into position but you may have to take of oilfilter and or adaptor but i may remember it wrong in
losen drivers side enginemount and starter then using engine lift or a highlifting floorjack and a big block of wood under oilpan, tilt engine over towards passanger side as far as it gets without using exesive force.
slide drivers side header in place from under the car (you may have to wigle it around alitle to find the right angle of atack but it will fit in)
lower motor back into possition and make sure header is clear and dont get stuck or bind anywhere, reinstall starter making sure the cables are not to close to primarytubes of headers boltheader to the head
hope it helps alitle i may have forgoten something but its not to hard just takes some patience
this winter im building my own headers will be intresting to se how to fit 2"primarytubes in a car with powersteering, but i dont think they will be as easy to install as some hookers ;)
