I will post a review, but I actually don't expect much more than just a little better than a "fresh" halogen bulb/lens.

 I know these bulbs are really old on Dad's 1066 and the when the setting is on "Dim"(low beam), for highway travel, those two front grill lights are really poor. I remove one of those front grill lamps, today and found it was only a two wire lamp, thus I can also install one of those Larsen light PAR 36 LEDs in there (I figured it might have been a 3 wire lamp, but it wasn't) 

Even if light output is only slightly better, I will still be happy, because I have lower the overall electrical load. Last year, I added two large LED (48 watt) at rear of cab, up high, for much improved rear view, for feed wagon operation. This tractor also runs the silage blower, and at night, those 2 48 Watt LEDs made a HUGE difference.

We will see, about these PAR 36 (18 watt) LEDs, some night.

Honestly, this wasn't my first plan; my first plan was two more of those 48 watt LEDs, on brackets up front, on 1066; BUT I stole those 48 watt LEDs to add lights to the front of my 300 gallon tank mounted in front of the 4440, for spraying, this Spring. So, if I still want more, I could still do the bracket idea, on the 1066, up front; But I want to try some of those 80 watt LEDs that Durallymax showed in his one LED review thread.