Engine reviving extremely high on ignition

1....First it is not fuel pressure. "Let's say" the throttle blades were perfect for idle speed as before. Increasing fuel pressure to the point that some fuel was forced past the needles/ seats and into the carb would cause loading up, smoking/ smelly idle, and idle speed normally goes DOWN if mixture is too rich

2....I would first try disconnecting throttle cable, take flashlight and look down into carb and see if you can tell for sure if throttles are seated / closed properly. Make certain auto / manual choke linkage is not sticking on "fast idle."

3....Inspect carefully any hoses. You have power brakes? It and PCV hose/ valve are no1 suspects. Try squeezing hose(s) shut with pliers/ vise grips

4....Try wiggling carb by hand see if you can detect any looseness