77 T/A 403 Perfomance upgrades

My short term goal is to upgrade my parts to a mild street set up.
The engine is an Oldsmobile 403 with a Rochester Q-Jet 4bbl Carb #M4MC
I plan to do the following work:

Remove Air Pump - Done
Remove EGR
Intake Manifold (Edelbrock 3711) - Bought
Mild Cam (Edelbrock 3712)
New Valve Springs (Edelbrock 5812)
New Timing Chain (Edelbrock 7813)
Exaust Headers (Probably Headman, any suggestions?)
Flow Master Exaust (any suggestions on muffler? should I use cats?)
MSD Ignition System - Maybe, yes if I decide to go for a more aggressive setup.

Probably other little engine parts replacement too, even though I don't need them because the engine only has 33,000 miles on it.

Any other suggestions?
What order should I do this in?