In '68, Chrysler put the Edelbrock DP4B aluminum intake into their Hustle Stuff (later Direct Connection and Mopar Performance) performance parts program, with a factory Chrysler part number cast into it. Think "Performer" in the current time.
The factory 4bbl on the 383 was a Carter AFB, which would equate to the Edelbrock AFB in current time. 1406 with the
electric choke, I believe? Check
www.edelbrock.com for the installation instructions for the Performer intake for the 383, for any extra required parts, like the extension for the existing kickdown rod on the trans linkage, possibly.
The '67 383/325 (4bbl) air cleaner was the "small circle" base plate air cleaner, as the '68 had the "Holley-size" larger hole in the base plate (as the '68 Road Runner did). You can possibly find one of the repro Road Runner air cleaners in Mopar Performance or at a swap meet. All you really need is the base plate to work with your existing air cleaner (same size filter). The other gain is the gap around the bottom of the top air cleaner part for an incognito open element air cleaner.
Use the "thick" OEM-style carb base gasket rather than the thin cardboard one supplied with the carb. You can probably find a pre-bent fuel line (fuel pump to carb) in the B-body reproduction vendors' fuel line selections.
From the power supply point near the power brake booster, you can run the electric choke wire along the cowl to a place where you can then bend it to run with an existing harness to the distributor area of the engine, along the inner valve cover. A little finesse can make it "invisible" to the unknowing eye. "Looking factory" rather than not.
In '67, the "4bbl cam", otherwise termed "Standard Cam" of the 383 4bbl (and 440/350) was expanded in use to the 383 2bbls. So, when done, you'll have pretty much the modern version of the 383/325-spec set-up. EXCEPT that in the '67 Chrysler models, the 383 4-bbl was a SINGLE EXHAUST engine, from the factory. Plymouth and Dodges got factory duals. ALL rated at 325 horsepower, though.
The Edelbrock intake and carb can be sourced from Summit Racing or similar. Look for the best pricing, even some sales every now and then. The OEM-style carb base gasket can be added later, from NAPA or possibly from the Holley parts catalog.
With the aluminum intake on my '67, I used the 440 6-pack paper intake gaskets with the factory steel valley pan intake manifold gasket in between them. Putting black high-heat silicone in the grooves of the valley pan helped it seal better, to me. Personal preference. You can re-use the existing intake manifold bolts, but be sure to put flat washers under them with the aluminum intake manifold.
There were different factory 4bb intakes each year, seemingly. I'm not sure which one might be the best, but probably suspect the '70-'71 vintage might be the better ones. There are some lists of the casting numbers online, possibly in several places.
When done, the car probably won't drive much different than it does now, EXCEPT above 3000rpm. The primary side of the carb is basically the same size as the 2bbl now is.
Other than the AFB-type carb, you can also used the Edelbrock AVS2 carb, with the more efficient annular discharge venture on the primary side.
It's all doable! Enjoy!
CBODY67