You just keep asking about a complete swap kit. Hate to break the news to you, but they do not make a "complete kit" that you can buy to make a swap.
You are asking about a V6 swap kit, but now you say an I6...Those are 2 entirely different animals.
The easiest thing that you can do if you want to swap a motor with a "complete kit" is to sell the YJ with the 2.5L 4cyl. in it and buy one with a 6cyl. in it. There you go! Complete Swap Kit!
'87 YJ, 4.2L built and bored, 8.5" of lift, 8.8 rear, AX15/NP 231, Tom Woods drive shafts, Flat fenders, 12,000LB winch, Custom bumpers, Rattle can paint job. Never completed...