I have those tail lights on our '72-1/2, and after 50 yrs the flash-plate reflector on stock tail light bases is essentially gone. So 'new' taii light are very bright in comparison. You need all the attention you can get with today's 'dashboard entertainment centers' on cars around you! I see where Tesla had to delete the use of on-board GAMING when their car is in motion! How boring the car must be to need all those distractions when driving!
Jack, if you can’t beat ‘em, join ‘em. Pantera Electronics has LED conversions for those GRP4 tail lights.