I think Melonie's assessment is pretty close to the mark.
Tiffany was roughly about the size of Traci Topps, possibly a little smaller. She had a thin frame, but fairly broad shoulders.
Traci was 36J, so I'd place Tiffany around 38H or 38I.
As WikiPedia says, it's fairly common for models and dancers to publish misleading measurements, or for magazines to publish wonky sizes to wow readers. Though some appear to make up measurements, a common middle ground is to give what appears to be a bra size (43G for example) but is actually a bra + cup size combined with a bust diameter.