Bolt pattern is identical.
OEM Gen 5 wheels: rear offset/backspacing should be identical. Front offset/backspacing is not…the extra 0.5” was added to the outside of the front wheels to account for the wider Gen 5 fenders. Gen 5 fronts will fit earlier generation Vipers, but will sit flush or maybe even a little to the outside of the Gen 3/4 fenders…this will make the rears seem too tucked for some, but that can be fixed with spacers to bring the rears out a little.
Aftermarket Gen 5 wheels: most aftermarket Viper wheels will fit flush with the fenders. For the rears, this shouldn’t be an issue (i.e., you should be able to run them on a Gen 3/4 without issue). The fronts, however, would be an issue. Aftermarket Gen 5 front wheels with an aggressive offset will most definitely sit too far outside for a Gen 3/4. I guess you could run some sweet mud flaps or something, but it wouldn’t be my first choice.
Bottom line: many Gen 3/4 owners have successfully swapped to OEM Gen 5 wheels. If you want to run aftermarket Gen 5 Viper wheels with aggressive offsets, I wouldn’t personally do it due to the typical front offsets chosen for that specific application (the lips would end up well beyond the edges of the Gen 3/4 front fenders).
Make sense?