Welcome to the forums man!
I have just about done it all bolton wise, and I have my "list" of things I reccomed to do first.
In order, these are:
ANY aftermarket shifter (I have a pro 5.0 W/ a steeda triax handle...LOVE IT)
Handhelp tuner (Xcal by SCT is what you want)
A midpipe (I would go SLP in your case...your choice of catted or not)
Then last but not least, GEARS. (3.73-4.10..I have 3.73s and love em)
Now the reason I put the tuner up before the mid pipe and gears, is because A. if you go with no cats on the SLP X pipe, the tuner can turn OFF the rear sensors....other wise your check engine light will come on.
B. because after marke gears throw off your speedometer...you can use the tuner to tell the computer that it has a certain gear ratio, and it will fix the speedometer.
Now as far as everything else I just cant say, until you say exactly what you want for the car in the future. Nothing worse than having excess parts....
and I wouldnt do weldin mufflers unless you just want to. You can buy a magnaflow catback on partshopper.com with the promo code "magna454" I think, for $350. By the time you buy two mufflers and pay the shop, its going to be about the same. You will gain 1-2 HP with weldins, vs 6-8 with the catback.
Good luck

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