How To Measure Fuel Volume.

Advancing the cam to 104 will shift the rpm range lower by about 200 rpm. It will improve idle quality & vacuum, but only by a small amount.

It also will improve the bottom with that large ish
cam and smallish convertor, which will positively effect the Et slip.
Will create more torque around where his convertor hits.
For a cheap investment, I would also throw a 4 hole spacer on the car.
Especially with the single plane on it.