That particular question can only be answered when we know the condition of the engine. If the bearings are still in close tolerance you can use a 10W30 or even lighter viscosity.
On the other hand, if the bearings are worn you should use a 15W40 or even possibly heavier.
The only way to know is to run the engine, get it hot and watch the oil gauge. If the oil pressure drops too much at an idle, go to a heavier (thicker... higher numbers) oil.
In general you want to use the lowest viscosity that you can while maintaining good oil pressure.
5 quarts
Viscosity SAE 5W-30 V6 Engines Viscosity SAE 5W-20 V8 Engines
The 4.0L V6 takes 5 quarts of oil The 4.6L V8 takes 6 quarts of oil
5 quarts with filter and you should use 10w-30 motor oil
A V8 engine
.035 is recommended
The recommended oil for the 2007 V8 Mustang is API "Certified for gasoline engine" Viscosity SAE 5W-20
10w30 the recommended weight.
The 5.3L V8 Engine requires 6 us quarts (5.7 liters) of SAE 5W-30 viscosity grade oil.....
The Chevy V8s are pretty interchangeable. Just make sure that the year of the engine is the same as the vehicle you are putting it in. Also if the Camero wasn't a V8 to begin with, you will have a lot of electric work and a computer change to go with all of the other mods.
2006 Dodge Ram 2500 with V8-345 5.7L engine requires 7.0quarts of oil. The recommended viscosity is 5W20. Note: the DIESEL 6 cyl 5.9 L engine requires 12.0 quarts of oil (recommended viscosity 5W40 synthetic).
According to the 2007 Ford Mustang Owner Guide : ( 5W-20 ) for the 4.6 liter 3V engine