you need to carefully pull down some of rear head lining fabric at rear of car
under here is a small nut that holds the aerial in place and the connecting wires that go off to the radio
unplug wires, undo nut, remove aerial from outside of car, replace base with new one, rubber seal etc.. use new nut to put it all back together water tight, reconnect wires, put head lining back carefully
head lining is the most fiddly bit of this job
p.s. ive never done this, would like to do so soon, as mine is flaking away also... so above is what I recon is involved
just ordered one from dealer, price is £13.00 exactly including VAT... I get 10% off parts so all is good
