The only legal and MoT friendly way is to fit upgraded halogen bulbs like these from Osram. Philips also do some
https://www.nightbreaker.co.uk/night-breaker-200?gclid=CjwKCAiA1aiMBhAUEiwACw25MSLggCBgN0lIys2xTZqyuNon-efZ_wW-ABDp-K6UMrDNzu9F_Pyx6BoCjHEQAvD_BwE