1. Leave plates on bonnet and wings and respray chosen body colour
2. remove lower edge checker plates as they're only ever there to cover up some known/unknown panel gout...unless you know all is well, then paint as body
3. don't know paint volume, but would be worth talking to Paintman, then add 10%
https://paintman.co.uk/
4. UPOL Raptor is available in body tintable, not just black. Simply buy Raptor 2k tintable, add 10-20% body colour, mix well and spray
I'm not a fan of bed liner paint on external paintwork but have seen some great rooking Defenders with bed liner sprayed panels. But I think this is down to bodywork colour...it would look **** in bright blue.
I Raptor tinted the complete underside of my Brooklands Green MGB V8, it looks superb and is tough as nails