No way would I go back to the stock factory smog 302 curve. It is very slow and not a good performance setup. The centrifugal curve has about 32 degrees in it starting just above idle and going up to the full 32 at 4400 RPM. The initial setting is 4 degrees so the total of initial plus all the centrifugal is 36 at 4400 RPM. There is also a ported vacuum advance that would add additional advance at cruise in the factory setup.
I have just done some work on my 302 curve and distributor to get rid of the smog style setup. I would advise you to remove some of the centrifugal advance from the distributor and replace it with the same amount of initial. Shoot for between 20-24 in the centrifugal and set your initial to 12-16 (depending on the centrifugal)to give you 36 degrees total at the top of the curve with the vacuum advance plugged. The centrifugal needs to be all in by 3000 RPM or so. The vacuum advance was set up as ported from the factory after emissions became an issue. Before that, they ran manifold vaccum to the distributor. Buy a NAPA VC1810 vacuum can for about $9.00 and run it with manifold vacuum from the power brake booster fitting. This will give you full vacuum advance at idle and the engine will love it. The temperature will go down and the idle will be stable. The tune up is the same as before except for the new initial advance setting but the idle will jump quite a bit when the vacuum advance is hooked back up. You will need to readjust the idle speed and mixture screws to make the switch.
Feel free to ask questions if needed.
P.S. - I am running 16 degrees initial with 20 degrees in the centrifugal that is all in by 2600 RPM with the VC1810 vacuum can and it works great.