Just finished mine today
Its not quite as straight forward as it seems, its quite fiddly so you need to be good with your hands, plus you'll need a dremel tool to get rid of the slats, bear that in mind.
Cost in total(for me):
£10 for grille(breakers)
£15 for mesh(ebay)
£14 for Grey primer and Satin black paint(halfords) Although its expensive for the paint, you get plenty left over which comes in handy for other jobs
£1 for adhesive(poundland

)
£40.. It may add up, but it looks so much better than standard, and in my opinion, better than the mesh grills you get on ebay.
The reason i didn't buy one off ebay is simple, i wanted to keep the Citroen badges up front.