In my case, swapping out the bulb with an LED was completely reversible. And a postscript to the above story.......the seller of the 736 told me that in going in there to put in the LED, I broke something. ????? Bent an axle? But I see your point, Adriatic. The things I've modded have been for the most part reversible (like this example) or if it's a quality engine, I leave it as is.
Roger