I'm not a camshaft expert, but there are a few things you should consider before changing the camshaft. The camshaft for the 4 barrel 350 was in an engine with a compression ratio of 10.5:1, yours stock is 9.2:1. I think the four barrel heads had 68 cc chambers and the two barrel head had 72 cc chambers. In order to see/feel any difference you will have to rev the engine faster, the four barrel with the 066 camshaft has a power/torque curve at 3200-5100 RPM and yours is 2800 to 4600 rpm. You will most likely have to idle faster than you do now to smooth it out, You'll also have to think about breathing, the 066 operates in a car with a larger CFM carburetor than you have, I don't know what differences there were in the exhaust but I imagine the four barrel had more flow. Then there is the rear axle ratio. usually the larger one goes with a camshaft the steeper the rear gear is.

I'm not saying it's a bad idea to switch but one has to think of all the other variables before changing one component.

As Wovenweb says, a valve job wouldn't hurt. You'll have to pull the heads for that. and this would be the right time to change out the timing chain and gears.. Check the condition of the push rods and rockers while they are out, they may need replacement. If you re use the rockers and push rods make sure they go back in the same position they came out.