this sounds daft but if your sporty blows
number plate bulbs every 2 months like mine try this,replace them with white
l.e.d.'s.the prob seems to be the heat
inside that thick plastic bubble,i burnt
my fingers getting one out so it's no wonder they blow.
the l.e.d is tec illegal but it gives the same light no heat and still passed the mot(16/08).
don't forget to chk its working b4 you
re attach the bubble as the l.e.d. is
polarity sensitive(turn it around)
one less job....