looks good. what about hard drive & optical drive? if you want an indash dvd you may wanna tell him before he spends 6 hrs sanding the bezel to perfection
also a note about fuses. the fuse rating should not be based on the power supply rating. the fuse is there to protect the wire itself from burning. that said you can drop the fuse size a little just in case and it should be based on the smallest wire in that circuit. for example I would go with a 10 amp fuse for the power wire (even though 8 gauge can handle like 24 amps continuous and normally you would use a 20+ amp fuse) if you go with a 10 amp fuse you protect the 12 gauge part (since 12 gauge is rated at like 9.5 amps continuous).
also an 8 gauge ring terminal will be needed for grounding bring one with you so youre not paying the guy 50 bucks an hour to go to best buy.