header question

Im just curious if it is possible to mount a flow daddy header meant for a 91-99 XJ to an 89 XJ. i have a pacesetter header on it now and the way it is made causes it to come into contact with my front drive shaft/pinion (violently i might add). but that pacesetter header says it it made to fit an 87-92 XJ so if my thinking is somewhat sane a header meant to fit a 91 XJ should fit on mine?

but if anybody knows if there is any real reason why not any help would be appreciated. thanks guys

You can use the 91+ headers on the 87-90 4.0--you have to add two bungs to the newer header, one for the EGR valve and one for the o2 sensor. Most any muffler shop can weld them on for you if you don't have the skills.

Good luck.