Corrosion / electrolysis under paint on bonnet and boot?

[Bonnyboy]

I am thinking of attacking the corrosion that has occurred along the edge of my bonnet (hood) and boot (trunk).  Rather than repaint the entire hood which I can't afford at this time I was going to try to grind away the bubbling, treat the aluminium and fill the void left with filler and then touch up the paint.

Has anyone done this and are there any good tips I should follow?