The easier way to distinguish them, I'd think, is by looking at the sponsors. The 97T is sponsored only by "GoodYear" at the rear wing's sides, while the 98T is sponsored at the same spots by "GoodYear" and "elf". The 97T is sponsored by "Olympus", the 98T by "Delonghi". The #12 on Ayrton's car uses different fonts for each model as well. The 97T reads "John Player Special" on its rear wing, whereas the 98T reads "John Player".