Body to frame mounts?

[CHaingKaiShek]

Anyone able to suggest the best way to replace the frame to body mounts which are located under the bed of a 73-87 1/2 ton truck? Hopefully there is a way to do this without removing the bed.

I'm getting some fairly nasty vibrations at certain RPMs, which could be either comming from the bed, or from the rear bumper. (I'm going to check the bumper this morning.) The rubber mounts however appear to be quite cracked and split, but are still in-tact.

So is there a way to loosen up the bed to frame bolts and raise the bed upwards via the use of a floor-jack before removing the bolts/mounts one at a time and installing new ones? (Replacing each bolt before moving to the next.

Jeff