hypnodoc said he was very happy with his car after changing all the front bushes for nolothane ones. im sure senna_t (pat @ wholesale suspensions) will be able to help with bushes as well
my missus mum is a teacher at a school who got some of this bullsh*t stimulous. they built brand spanking new classrooms that weren't needed, and because by some miracle after the ridiculous prices charged for those buildings there was money left over that had to be spent, they ripped up 1yo carpet and relaid it. such a huge waste of money.
try driving the car without any of the airbox, just the pod, and see if it makes the same noise. if the pod is part of the box, just remove the bottom half. It could be the plastic box vibrating if you have cut holes in it.
for the falcon I was quoted around $350 labour to install a clutch, take from that what you will. call a local mechanic and get a quote on the install, they will be able to help.
I would check the tightness of the bolts holding the stick in place. these came loose on my car and I had similar problems to what you describe. there are 2 12mm (iirc) bolts just under the leather boot. you should be able to lift the piece of the console straight up by getting your fingers under where the leather meets the plastic.
once your under there you will see what needs doing. I'd start with the interior/shifter, then exhaust, tailshaft etc. then crossmember. be sure to support the back of the gearbox as you are removing the crossmember because the thread can easily strip out of the bolt holes.
you need less than 2L of oil for the diff so I wouldn't be buying it in bulk for a 6 monthly change.. I used redline 80w140 and it tightened the diff up alot. mine was a bit sloppy with castrol oil in it.