LED blinkers and resistors

Hey guys, so I'm puttin LED blinkers in the rear and I know I'm going to need some resistors to make the wiring think that I've got a functional bulb back there so they flash at the normal rate.

anyone know what ohm resistor I need to make it work properly?

Thanks

Just got to Radio Shack a get some 8 Ohm, 20 Watt resisters and you'll be set.

What size clear lens are you using? I was thinking of doing the same thing myself, however I dont know what size lens will work without some serious mods.

Thanks

I'm not modifying the stock ones,

I just got these crappy ebay flush mounts:
(right now I just have bulbs hanging by wires)