904 shifts too early

When I bought the car, the trans had about 1800 miles since rebuild. From a dead stop, the car will shift twice before you get 40 ft. Will hold in first or second gear manually with no problem....shifts are crisp. Not sure if there is a adjustment similar to TV cable on later model cars? Thought I'd check here before toting it off to the transmission shop.

Not sure about this linkage setup. The throttle linkage is baaaarely ling enough to let the butterflies close completely.