You need to modify the distributor mech curve so it is shorter.
typical is 20-24deg . you want a 10deg curve.
this allows 26deg at idle and 36deg at max mech advance.
Then:::: vacuum advance should be about 10deg at hiway cruise. and limited to a max of about 12-15deg at max.
These are separate issues requiring separate advance system tuning modification.
The Qjet will also needa power piston spring swap to keep it from loading up in gear when idling in gear.
This lighter tension power piston spring keeps the pri metering rods down/lean at idle.
( edelbrock or carb shop Qjet tuning/service part)
A stock very low stall converter will not work.
Especially he GM 13" converter. Get a 10" 3000+stall. Or change the cam.