new stainless exhaust (a bit cumbersome when by yourself and only wheel ramps and trolly jacks to aid you).
dump valve (optional), ICE, steering wheel change (RS 3 or 4 spoke)(momo sparco etc).

Best thing to do is write down exactly what you want to do, plan everything out, so if your going to change your head unit - and at a later point your going to put in some switches to turn on some neons for example - then while your fiddling around with head unit, get your switched live from that circuit and run the wires to the places where you want the switches in preparation for that. It will save you hours later on, but take more hours in the first place, but it saves you taking a head unit out just to get at a switched live.

If you fail to plan, you plan to fail.

Most bling bits from auto specialists, however the bottom end stuff like altenator shield might prove a tad difficult, but if you have paitience then go for it.

Anything bodywork related, leave to pro's.
Anything your unsure of, get a haynes manual.