I know you asked for concrete evidence, but I'ma give you what I understand about it (definitely not concrete). I've never done a 4.0 swap though. In 96 every car switched to OBDII (EEC-V for Ford) diagnostics system. Prior to that Ford used EEC-IV (OBDI). This causes issues because it requires you to swap basically everything from the Explorer. In 1998 (I think, again, not concrete) Ford put PATS (passive anti-theft system) into the explorer. This causes a whole metric fuckton of issues for people trying to do a 4.0 swap. Wiring galore and all that jazz. Basically, from what I understand, a 1995 and older explorer should work, but the issue with a 95 is it has a different dashboard and cluster than the 91-94. I can imagine this would cause some issues. If I was gonna do it (hopefully will one day), I'd get a 91-94 explorer and swap the engine, keep the BII dash, swap in the Explorer cluster and ECU. Do whatever wiring I gotta do and call it a day.