As far as legalities go, there should be no problem with lights marked ADR Compliant. On the other hand, fitting LED bulbs to existing fittings is almost certainly not legal, and you will find that the suppliers of these mark them "for display, offroad etc" or something similar. Similar situation to fitting HID bulbs to headlights not designed for them.
On the other hand, the only time they are likely to get detected is in the event that you give the authorities an excuse to go over the car with a fine tooth comb. Something that I have never had happen in over fifty years of driving.
John
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
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