Low Rpm Misfire vibration and weird *** rattling noise

hey guys so i got 2 issues, i got a low rpm misfire vibration around 1000-1500 rpms in park you can feel it in drive it gets more noticeable, i seen that my spark plug cables were arching on the passenger side cables are pretty new, even swapped those with other ones and still has that misfire, although some cables are just touching the valves cover i dunno if thats an issue thier not touching the exhaust manifold.

Second Issue , lol some times when im driving and let go of the gas i hear a rattling noise like if my driveshaft if hitting something, it sounds nuts. then when i give it gas it goes away and comes back randomly i checked the driveshaft no marks, took the brakes a part nothing loose in there, and readjusted the axles 8 3/4s .