While your at it get the rear number plate bulbs aswell. You are replacing capless 501 bulbs with capless W5W led bulbs.
About 2 quid a pair on ebay. Make sure you get short ones for the rear. Piece of pi $$ to fit.
Don't bother fitting LEDs to the sidelights as they will fall apart with the heat from the main bulbs. Have a look at this link, I found out the hard way!
Use PIAA Xtremewhite H-222, been in for over a year and still look good.