Kurt,
Go to JC's site and search on something like:
mount
or
transmission mount
I got about four items displayed.
I cannot do this on the tablet I am using. JC's site unsurprisingly does not display a search box in Safari on an iPad. When I get on another computer, I'll try to post a link to the search results.
My post about those parts is partially facetious. Jim Carter is one of the vendors that lists a transmission mount for 1954 trucks - his site is wrong. In addition, I further lack confidence in his listings because of the dates listed for that one mount part. I bet he sells very few of those pads for the relatively rare 1767-1775 Pre War (revolutionary) Ticonderoga Series Chevrolets. To top off this silly situation is that there is no photo for a few of the transmission-mount parts on his site.
Here are some transmission mount listings:
Classic Parts - full mount assembly - incorrectly labelled for 54.
Classic Parts - pads only Chevs of the 40s - full assembly - correctly labelled for use through 53
Chevs of the 40s - pads and bolts - says through 54, perhaps because they know it can be used on the 54 Hydra-Matic transmission's rear mount (it worked for me).