before i get too far? chance would be a fine thing!!! ha ha!!
but to answer a few of your queries mate,
1 - its a make it up as you go job i'm afraid mate
2 - i don't think so, but i think you'll find most quality paints will do the job pretty well if the prep is good
3 - if its silver you want, paint them, lacquer will tarnish and turn yellow eventually and look horrible i suspect
4 - the most i'd do with carbs is clean and lacquer, but even a hint of petrol fumes around them will repeat the above, tarnish
5 - i think if i recall correctly, when kev did his 16v sud, a 16v rad is actually less volume, and more hassle to fit, so a recored sud rad will do just fine mate i reckon.
hope that helps, and of course if i'm wrong on any points i'm sure there'll be more opinions along soon,