If it's any help, the attached (hopefully!!) pic is from the company I use for all my LED bulbs, not the cheapest, but the quality is superb. I changed all of the bulbs on my 400, they even sell a LED headlamp bulb which fits the original light unit. I also purchased a flasher unit from them, it's about the size of a relay and fits into the rubber holder for the original, you can mix and match the bulbs and the flashing rate stays the same. All of this has given me nice bright lights and an easier life for old wiring. Have fun. Mike.
PS. The little green LED bulbs fitted inside the clocks are the icing on the cake.