yep, quite right Pete, even the stillens needed modding, although I didn't need to flatten them,only grind part of a weld and fit both o2 sensor bosses, only had to do 2 trial fits to the drivers side and once to the passenger side. some of the original manifold bolts are a bitch to get at, I think I was lucky because all the nuts came off with no problem.I also found that the passenger manilfolds go in/out no problem without having to remove anything, but the driverside is easier with the starter motor off and out of the way and be very careful not to break the o2 sensors. Still if you know what your doing and have the tools to do it, then it isn't a hard job.
Pete