new by and looking for suggestions

Hello and looking for some good tips as I'm a newby to this.
I have a 1970 LTD 429 2v with 10.5 to1 comp got 320 hp and looking well maybe 400
Its going to be a sunday driver with a little power and nice sound

I'm looking for a manifold that would be a bolt on for a 4 barrel carb
I have found this manifold
Edelbrock Performer Intake Manifold Ford 429/460 Stock Heads 2166
or can any one give me a part no or link and same as for a carby.
I was looking at a 750 cfm carby

next I was looking at these for mufflers
FLOWMASTER HUSHPOWER SUPER HP-2 MUFFLER FLO12512304 OVAL 2-1/2" IN/OUT 18" LONG
( 162065642729 )

either a set of these headers
Hooker Headers 6224-1 Super Comp Engine Swap Headers Ford 429-460
( 400301108595 )
or these
STAINLESS SHORTY HUGGER HEADER EXHAUST MANIFOLD FOR 429/460 FORD BBC BIG BLOCK
( 231981877241 ) but not sure which will fit

the cam currently has a lobe lift of .253/.278 valve lift of .442/.486 opening at 16deg
inlet dur 256 and ex dur 270 at 36 deg overlap
hope this info makes sense to you smart guys
so a cam I was looking at is a comp cam with the following info
comp cam pt no 34-226-4 grind no 265DEH
or a 34-227-4 grind 268H
hope one may slide right in

Now a dizzy
looking for help here

looking forward to your help

Your best "seat of the pants" improvement will be to put a higher ratio gear in the rear.

That Edelbrock 2166 manifold is good for your application having enough under-hood clearance giving good power above 2,500 RPM.

Use some Magnaflow mufflers; the largest which will fit under your car.

I'd use a Comp Cams 34-244-4 however, that 265DEH will be a good everyday performer.

If weight isn't a problem the factory 4v manifold would be a big improvement.