| Depends what you mean by hard to fit? You have to do a bit of dismantling, the most hassle I had was removing the bulb holders from the back of the clocks without breaking the wires. Then it depends how neat you want it all to look - I wired mine in by taking the pins out of the plugs and soldered the extra wires in, using heat shrink sleeving. There are those that would just bodge the wiring with scotch locks - it's up to you!Adjustment? The first l.e.d. comes on at 6 1/2, then the next at 7 and so on until they all come on at 10 1/2, there is a screw for altering it, if you want, but that would be a bit of trial and error, not difficult though, and a damn good reminder to shift to the next one when you start getting carried away!
Mine was a present from my wife, bought from Tecmoto some years back, cost around £150.00! | 
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