setting timing with a new hei

[rennalds]

Ok so just installed a new msd hei dizz, i want to find out the best way to set timing for a completely stock 350 in my 71 cheyenne. we dont have a tach so i am just wonderin what the timing should be at idle with vac advance disconnected n plugged. also is the factory setting for the dizzys vac advaance ok to roll with after setting initial at idle, jist tryin not to damage anything, thanks for the help