727 vibration

Car ran very smooth, only has 82000 miles. it a 79 Chrysler 300 with 360. Transmission got a bad leak , whick ended up being the front pump cover. Transmission was taken to a trans shop for a inspection and seal replacement, trans shop replaced anything that was worn with a rebuilt torque convertor. Has a new trans mount. Car still has vibrations when you bring RPM's up. Even when you drive it. Nothing else was changed. Flex plate is still the same one. As said before, had original torque convertor rebuilt and replaced the one the was put in the first time and still have the vibrations.