Fitting additional high-level headlights to a U421 or U406 to improve the lighting and provide proper illumination when front implements are fitted.
Further information:
Bulb fittings and links to eBay for LED equivalents (I have no affliction to these sellers, just examples of where you can buy these LED bulbs).
Headlights: fitting P45T
https://www.ebay.co.uk/itm/204817051394?var=505477370478
Sidelights: fitting T4W
https://www.ebay.co.uk/itm/167157650343
Auxiliary lights (raised headlights): fitting H6
https://www.ebay.co.uk/itm/387658933032
Stop/Tail lights: fitting BAW15d
https://www.ebay.co.uk/itm/202180674539
Indicator bulbs (LED flasher unit required): fitting BAU15s