FAT carb

Most carbs come with 6.5 power valve.(TAKE IT OUT)

When you run a engine with that big of a camshaft, you have to use a 2.5 power valve.
You said you have 5 inches of vacuum at idle,SO THERE'S YOUR PROBLEM.
YOUR DUMPING ALL THE FUEL YOU WOULD USE ,IF IT WERE AT FULL THROTTLE, IN THE ENGINE AT IDLE.(very rich indeed)

Change your power valve to a 2.5 and set your mixture screws one full turn out to start.
Use a vacuum gauge and try to get the highest reading of vacuum at 1000 rpm's.
1000 rpm's is not to high of a rpm with your camshaft and for the best street manners you might want to set it at 1100 in park and 950 when in drive.
When it is set up right, it will only drop a little rpm when put into gear.
The least amount of rpm drop is desired when going from park to drive.
GOOD LUCK :burnout: