Hyper flashing can be solved by changing the flasher relay
(assuming it is replaceable). On some (most ?) newer Ford vehicles, the flashing is controlled by the BCM/"Smart Junction Box"/or whatever they call it these days !
A resistor kit defeats the whole purpose of switching to LED in order to reduce the current.
EDIT : This
bulletin applies SPECIFICALLY to 2008MY Super Duty F-Series. It states that the flashing rate CAN BE ADJUSTED by modifying parameters inside the Smart Power Distribution unction Box processors.
I am not sure when this happened to E-Series.