You do realise the locked timing is for testing purposes only?
What was propose by fbird is the same as jamming a stick under the front door to let fresh air in the house.
Basically,take off cap and rotor
play with advance weights to make sure they move
Advance them with your finger by pushing the weights away from their resting position until they are fully open
Jam a nylon pull tie in where ever you can fit it and attach 2(1 to each weight)
This will "jam" the weights fully advanced.
set timing to 35º
test for ping when accellerating from stop
test for part throttle drive ability
carb especially idle will need to be set before driving
Make sure you trim loose ends from nylon pull ties before installing cap and rotor
While the cap is off:
Take float bowls off carb and note front and rear jet sizes and power valve numbers.
numbers are stamped onto both parts.
alse note if rear of carb has a metering block or plate
Do you have a holley?
If its a carter/edelbrock,take out the metering rod and check number