Depending on what header you have on it, you can get a down pipe for a TJ 4.0, and it will go around the front of the oil pan instead of crossing over behind it like a YJ does.
Its a thought. It will protect your pipe better (less likely to get dented) but it does make it a PITA if you have to remove the starter.
'87 YJ, 4.2L built and bored, 8" of lift, 8.8 rear, AX15/NP 231J, Tom Woods drive shafts, Flat fenders, 12,000LB winch, Custom bumpers, Rattle can paint job. Never completed...