there are issues with messing with the fan.

I had to bolt my pulley on and cut the extra threaded bits off the studs.

once you have a fan, relay, temp sender, then you need a way to mount it, if you're not using a fan from another car then have fun making a new shroud. why? well if you use those handy mount the fan directly to the radiator things and live somewhere bumpy, your radiator will break, and it won't happen somewhere where it's easy to deal with.

so you got all that, :) my fan pulls over 30A at startup, i've seen it pop 30A fuses instantly. mine is wired more or less directly to the battery through a relay so it only runs when the car is on.

Adding a light is a good idea, as is an always on switch. I don't think an adjustable fan controller is worth using.

if you don't use a relay it will work for a while, but the thermal switches burn up for me because of the fan's power draw.

i have a standard 60A alternator and it works fine, but up to a point more is better.

if you're concerned about the alternator drag, you could rig up a bypass that takes the alt offline, yes you can do it, and it will free up a little bit more power ( about 600W for you KW people ) you can tun the car for an hour - several hours depending on electrical draw like that.