Take a bolt with a 13mm head on it and place it between the frame and mount rubber base ..if it won't go , the mounts have collapsed to the point that replacement is needed for correction.

And it is always good to do tranns mount at the same time b/c new mounts change the drive-shaft geometric angle with the new monts and old trans mount. That causes vibrations AND pre-mature flex disc wear..................

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A Dalton