Engine jumping in bay during acceleration

Sitting in neutral my car runs perfect and can rev through all ranges in stride.

i put the car in first and go to accelerate the car needs to have the clutch feathered a large amount cannot let it out more than about 50%.

If I give it very slow throttle and work the clutch I can get out of first then have to do it again with second then third I can let the clutch out fully and forth I can shift into with no issues at all.

but going up hill or over bumps or letting the engine hit 3000 rpm with my foot off the clutch the engine starts jumping again.

i replaced the rear engine mount thinking that was the issue could the front mount be bad and is why it is still acting this way?

my thinking was that when the rear mount gave out the jumping of the motor was to much for the front mount and ruined it as well.