I found the following images while browsing through the textures in gta3.img, the topfun.txd (which is the texture file for Berkley's RC Van) contains four compressed DXT files, two of them are regular textures such as wheels and interiors directly copied from the Pony's texture files.The other two, however, are commercial posters that I think appear in Zero's shop.
Two of the vehicles in the posters caught my attention, one of them is a boat that never appears in the game and rebemles the Ferry from GTA LCS, GTA San Andreas did have a lot of cut features that were reincarnated in GTA Liberty City Stories so it wouldn't surprise me if that was the case. The other one (behind the bike) looks like what might have been the beta version of the Hydra, though it's hard to make out what it's really supposed to be.
Have a look for yourself and share your thoughts.
