auto and manual are very not the same
i think i have such a thing but any flywheel from a amc 6 or 8 cylinder engine will fit the vibe you refer to is poss due to the engines being balenced from the front by the rubberised harmonic damper the truth out in the world is mostly there is no vibration and if there is its barely noticed and happens at 700 1100 rpm and feels like there might be a misfire that is not therethe answer if you are worrysome person is to get an engine shop to balance and face it
use the I6 flywheel/clutch, I have on my 360 and so far not caused any issues
i have had a few v8 jeeps and never owned a v8 flywheel as they are very uncommon here in the uk i have always used the i6 one and never had a problem
the tube headers i have at the moment will be spare soon, should get the engine swap done in a few weeks and will be giving Kev back his fewnderwells and I'm thinking of getting cast or shorty headers so i can run the pipes inboard of the chassis rails this time, last time I ran the CJ off road it lost both side pipes over the weekend