1968 Slant Six Dart Survivor

Nice clean looking car! There are many things I see that aren't original or stock. You mentioned some of them already but I'll list the ones I see. You can get date coded hoses but unless you're going to show the car in a strict class, don't bother paying the premium for them. Here are the items I see.....radio (and cut dash), belts and hoses and clamps, fuel filter (those plastic ones can crack or melt you know...), alternator, voltage regulator, radiator cap, exhaust manifold, battery, and maybe the carb (I see an extra vacuumn fitting that's been capped for some reason). The loose wire looks like the one that goes to the oil pressure sender which is down under the oil filter, threaded into the oil pump housing. The exhaust manifold nut and washer are what's missing on the rear stud. they are special to the end studs only. They take a brass washer with a beveled inner hole and a castleated (sp?) nut that mounts up-side-down from what you would think. I can't see your front one so I don't know if it's correct or not. That needs to be installed as soon as possible or you may warp the exhaust manifold causing a port misalignment. There may be other things but that's all I notice right off hand with the photos you've posted.