Huh? Not sure what you want to know,,,
If you're asking what year Ex has a 5.0/302, then it started in 1996 and went thru 2001.
On Mustangs the 5.0/302 was made until the 1995? model year. Then they went to the 4.6.
As far as swapping them over, you must remember the wiring harnesses are all different, dash etc. But a 302 swap into a 2nd gen Explorer isn't that far a stretch; however most people say they would rather just simply buy a 2nd gen with a V8 in it to begin with rather than spend the time and money swapping one in.
96-01 Explorer 5.0's use basically a GT-40 head setup, which flows quite well; I believe that's the same heads that were on Mustang Cobras between 89-93 or something like that...