Not sure what this would do weight-wise but maybe consider ripping out the trunk and getting it sprayed with like Line-X or some other spray in bed liner? Waterproof, Durable, Clean, and it probably would have some sound deadening qualities.
As far as the interior goes, maybe some LED replacement, white face dash applique? You could probably always swap out the seats with something else and give you a bit different of a look.
Not sure what this would do weight-wise but maybe consider ripping out the trunk and getting it sprayed with like Line-X or some other spray in bed liner? Waterproof, Durable, Clean, and it probably would have some sound deadening qualities.
As far as the interior goes, maybe some LED replacement, white face dash applique? You could probably always swap out the seats with something else and give you a bit different of a look.
I agree I would put in some LED Dome lights for some extra color and replace the gauges. Some chrome interior accents wouldn't hurt either.
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-A7X- ~Stang Syndicate Boston~*2006 Torch Red GT*10/10/07 Performance:Borla FRPP Stingers w/ True Dual Midpipes, Magnaflow High Flow Cats, JLT CAI, Bama 93 Race Tune, Ford Racing 4.10 Gears, Nitto 555 Extremes. Visual: Black AVS Tail Light Trim, Honeycomb Tail Light Vinyl, Black Racing stripes, 35% Window Tint, Trunk Blackout Panel, Billet Antenna Delete, Mirror Covers, 17" Konig "Further" Rims, Quarter Window Louvers, 20% Tinted Head Light/Turn Signal, Boss C-Stripes, CS/GT C-Scoops.
How about a local car upholstery shop... go and ask for some references... and best yet... go to a few car shows, see one you like, ask the owner where they got theirs done... It's a big step - so take your time!
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The greatness of a nation and its moral progress,
can be judged by the way its animals are treated. ~ Gandhi
I bought roush leather seat covers/foam online and then asked the local ford dealer who does their installations, then had that place install it.
The shop had to make new foam for the headrests because the new ones were a different shape.
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2004 3.9L/auto
-Mac CAI, 73mm Mass Air
-Dual Flowmaster 40s, H pipe, 2.25 in pipe
-42% Underdrive Pulleys
-SCT Tuned
-4.10 Gears & Trac-lok
My Trunk lining is Horrible, My Interior boring 
It's a big step - so take your time! 
