Cam suggestions for 5.9 Magnum in Canyon/Road racer?

That is a nice torque curve on that Hughes cam, though. Another consideration is if you're converting from a magnum front drive to an LA front cover. If not, you'll need a Hughes bolt and washer kit if you use an LA cam.
https://www.hughesengines.com/Index/products.php?search=7011&partid=11253
If you switch to an LA cover, you can use an LA hydraulic roller cam or core. I've done 360 LA in a 318 5.2 magnum once and the extra lift with the magnum rocker arms made an incredible grunt torque truck engine. We used early 318 truck manifolds and a chinese air gap intake with an Edelbrock 600. If you need an LA hydraulic roller core, post up a wanted thread here in a separate listing. One thing to consider with the Multiport EFI, though, is that they usually work better and are more forgiving on the tune with a 112 or wider LSA. I do recommend the 2.74:1 1st and 1.55:1 second gear set from an a999, A500 RH42/RE42 transmission and a custom converter. If you can go with that, Oregon Grind #1236 looks good from here. 224/[email protected], 274/[email protected], .554/.563 lift (with Magnum 1.6:1 rockers) on a 112 LSA. Almost identical to that Hughes grind in the dyno article. One question on the Edelbrock Multi Port; Is that the Pro Flo 4 EFI with the super victor intake? I would stay with a single plane for that system, but would be considering having an Edelbrock Torker2, Weiand Xcellerator, or Holley street dominator modified for the EFI rails. Edelbrock lists that manifold for a usable power range of 3500-8500, even in injected form. That may shift downward some with the fuel inlet point moved to the intake port flange, but that's still a lot of volume for something you want torque right now with. A 4150 style injector on an air gap manifold may be a better option.
Super Victor EFI Intake Manifold for Small-Block Chrysler LA Series Engines
So originally I was going to keep my carb and manifold, and the Jegs Magnum comes with a LA timing cover and fuel pump eccentric. So I'm assuming it has an LA cam in it? I need to pull the cover and check, possibly it has the cam extention on a Magnum cam? The 904 has just been rebuilt so whatever gear in it is staying for now. The rear is a 8 1/4 with an Auburn in it, acrtually 3.21 or 3.23. Much better than the 2.45 the car came with. I had a A500 and a disc brake 9", but with a 15 day escrow not every thing got on the truck. I have the Edelbrock multi port already so we will see what happens, and yes it's victor super so now hood issue's are going to come into play.

Thank you everyone for steering me in the correct direction, Mike