i believe scott had to get a new ecm when he did the 4.0 swap in his yj. the donor cherokee had the anti theft system built into it.
cheapest way is tot get an ecm without the antitheft in it, or more expensively, get the ecm you have reprogrammed. no way to 'wire around' it as far as i know.
1998 XJ on 37's.JK Rubi axles with chromo shafts and ctm's, 4:1 transfer case, etc etc etc.The Cherylkee....
2003 Range Rover HSE, 4.4 Quad Cam.
1998 Range Rover 4.6 HSE
2000 4.7 4WD WJ with a rebuilt motor.
4.3/700r4/new frame buildup (YJ)....
Years to gain the hands on experience, and offer it freely.
Minutes to gain the knowledge from the internet, and quote it just as freely.