@border you do love to live dangerously don't you? Asking me serious questions when I am on "silly". So I'll swallow a drain rod and get serious.
The kit for the work lights will expect you to have two I'd a thought, and anyway they will only be no brighter than say two driving lamps, so yes, one relay will be enough for two lights.
Love dieseldogg's idea of switching them from the reversing light wire. Brilliant. Then you cannot drive off illegally with them still on. But in order for them not to come on every time you put the lever into reverse, you will need another switch in the wire.
But you still need a serious feed.
Personally I'd run a fused feed from the batt or some other point that you can expect to provide a lot of power, look for stuff with a high amp fuse. Maybe from the accessory plug wire. The fatter the brown wire, the more power it will be supplying. (Oops, a bit silly again)
As for the blower, the power the blower uses will be higher for a short while when it is first switched on then settle down to a lower power consumption. Power is measured in Watts, which is the following sum, Watts = voltage x current. So 12 volts times 6 amps = 72 watts. You cannot sensibly get more than 12 volts to much on a 12 volt vehicle, obviously, so the current flowing through the thing you are powering up decrees how much power it can use. If the power is high but you try to draw it through too thin a wire, the wire heats up and this means its initial resistance gets even higher. So eventually it burns through. This is how a fuse works. It is designed to blow when too much power is drawn through the circuit. This is a safe way of doing what I just described, rather than letting some part of the wiring burn through and possibly set fire to whatever it is near.
A relay allows a thin wire to be used to switch bigger power than it itself could handle on its own.
The thicker wires to the relay provide the big power to the blower or whatever while the two thinner wires simply do the switching.
Google "how an electrical relay works" to get a better explanation, as I am not a physics teacher!
https://www.google.com/search?q=wir.....69i57j0l4.6089j0j8&sourceid=chrome&ie=UTF-8
As for the wire gauge to your blower, does the kit list the actual gauge of the wires that come with it? I just looked, no, is the answer, although the fuse is 15 amps and the relay is 30 amp. So 15 x 12 = 180, i.e. the fuse will blow if more than 180 watts is drawn through it. Now the blower is fused by a 20 amp fuse, so peak power must be under 240 watts. Your existing 30 amp relay is therefore fine, but you cannot use the same kit for the blower.
But you already have a switch and a relay. The problem is the wiring.
You already have advice about how to sort this out. Reread it and remember you need to test both sides of a connection to see if it is sound or not. You have power to the relay, you have a switch that works and the earths are sound. So it looks to me as if it is the relay itself or the relay holder that is the problem. That it where I would look first, for bad connections. but I'd test the relay by taking out a known good 30 amp relay from somewhere else like the headlight washer relay and replacing it with the one you have for the blower. If the head lamp washers work with your blower relay then you know it is good.
Then you can check every single connection on the relay holder. Go back to the previous thread on this and use a paperclip opened out stuck into the 30 and 87 female slots in the relay holder, if the blower now works, with no other connections, you know the connections there are OK. Which more or less tells you that the problem is to do with either the switch, or the feed to the switch, or the wire from the switch to the 86 slot, or from the 85 slot to earth. all of these can be tested with your meter. Use volts first to see if you get live, which you'll only get once the key is turned to last but one position, then use it set to resistance, ohms across each connection, across the switch and from the end of the earth wire to the switch to the earth or another earth. These should all read nearly 0 to prove you have a good connection. The switch should show 0 ohms when "on" and be infinity, when the switch is "off".
If the relay is good and rhe relay holder is good, then it all should work and work safely.
I think this is enough for you to be going on with, it is for me!!
