DIY cab/bed bushings/mounts??

[RPBurris]

My 69 is sitting on a 79 chassis. The PO has a mix of steel pipe and whatever else he could find to mount the cab on the mounts. I want to replace the cab mounts,bed mounts, rad support mounts but not sure if any kit will work because of the modifications. Has anyone had success fabricating their own bushings of any kind? I have heard of old schoolers using hockey pucks but not sure if this is a valid option. Thanks.