Gearshift cable damaged or out of adjustment ? Check the plastic clip it's suppose to snap on that bracket . You could also try popping the cable off , and shifting manually . Don't overlook safety
. Have you tried slowly shifting it to reverse , then neutral to see if it will engage in gear ?
Parking sprag could be sticking , rear band mis-adjusted , valve body malfunction , rear servo malfunction , direct clutch in the overdrive or front clutch burnt . All from the service manual but , if just rebuilt , should have all been serviced and checked