360 Magnum building on an existing bottom end

So I have the intake and carburetors and the ignition bits. Does anyone have a preference on head or cam choice for this build. keep in mind that budget is a factor. I saw close to what I want to build on a web page called Dyno proven 360 packages, Package 9 is kind of where I want to be.
It states (360 rebuilt with 10:1 compression flat top cast pistons, original crank turned .010"/.010", rebuilt factory rods. Factory windage tray installed. 2.02" heads with competition valve job and ported to flow 260 cfm. Intake, port/gasket matched. Holley H.P. 750 (.076" front, .080" rear jets). Large 1 3/4" primary tube headers. Comp Cams 305AH-8 camshaft with .525"/.540" lift and 305/312 degree advertised duration, 253/260 degrees @ .050", 110 lsa, installed at 108 intake centerline. 495 h.p. @ 6,000 rpm 500 lbs. of torque @ 4,500 rpm)
I realize this isn't exactly what I'm building, but with the motor being almost full roller with the tunnel ram and dual carbs, I think I can hit or exceed those numbers. I also planed for 3.73 gears in the rear end. Do you think they are to low or not low enough, considering it will be mostly a street show car. I am building it in a 60's Gasser fashion.
Sound Good, I have a similar
On a budget....Get the cam reground by Oregon Cam Grinders. Give him your goals. Inspect, clean and Re-use lifters. CR is more like 9.2:1 with thin head gasket and stock pistons. Inspect bearings. As the Professor said.....Heads are a question mark. Home port factory heads if in good condition (no cracks) but will have smaller valves. Use Hughes 1110 valve spring kit. Stick with factory (non magnum) ignition.

Edit....I believe Indy makes a 2x4 Modman intake with carbs and linkage for Magnum.
Ckeck retainer to valve guide clearance, my magnum has only .20 thousandths clearance with Hughes springs/ retainers from the bottom of the retainer to the top of the valve guide.
, with A 512 lift cam