The 95 will be much different than the OP 06 Ford, which probably doesn't have a replaceable flasher. If you do have a seperate flasher then you would be able to replace it and solve any fast flash issue. But I would be very surprised if you had a flasher. But, maybe cab-chassis are different than the P/U trucks.
I installed those tai lights on my last TT and they are very bright and easy to see from every angle.
Personally, I would just go for it and if you have fast flash issues, get a couple of resistors off eBay for that purpose. It would be worth the extra work.