My MKIII - My Project - Need a few answers

[Scionguy]

ya the cat is part of that 3" youll want a resonator, and a good muffler or itll rasp. turbo's dont need headers. technicaly thats your downpipe, if you replace the header, its guna be to use a bigger turbo. i would buy arp head bolts to torque down your head, your stock ones may already be strecthed, if you wana do it right, replace the head gasket or go metal head gasket, but thats pricy and needs some head work. that oil in their is probably from spill, and those really big allen bolts ya know, they go right to the head, you pull one out and you can see oil and all that stuff, thats where mine leaked, your valve cover gaskets may be leaking too, just loose or cracked. o, no power chips lol, piggybacks yes, chips no.
this is what it looks like without valve covers, and this is wha a blown head gasket looks like


changing that gasket isnt easy, but it isnt hard either, mine was a bout 2 days of work total, and ive never done it before, but im pretty mechanically inclined.