Bed Specific units

Are the units bed specific? Like a short unit would fit any short bed? I.e., 1998 Tacoma or say a 2020 Tacoma? Thanks

I could be wrong but pretty sure that it’s truck specific in bed specific. So a 5 foot first GEN second GEN and third GEN would be the same I believe. But you could probably call GFC or email and they will give you better details.