if ur going to do any wiring for the love of god shut off the power in ur house especially if ur looking to a book for advice. As far as lowering temps im not really sure what else u could do, More fans usually equals cooler grow room, Can u raise the lights? If so they would keep the plants a little cooler. Ur temps dont seem to be that bad in my opinon. People can Disagree all they want but ive sucessfully grow white widows in 98-101 degree heat, very good bud. Temps are correct now and bud is better, but if u cant correct it its not that bad to live with. Also a cheap way would be to freeze a block of ice in ur freezer and put it inside ur room in a container of some sort, lowers ambient temps around ice creating a slight change in overall room temp
Oh God, yes! Believe me, I have a terrible fear of electricity. I'd probably shut off all the power to my house just to be safe.

The setup is all complete, I'd probably just end up rewiring whatever new thing enters the closet with old stuff, so I'd just be swapping out the +, -, and grounds.
I've added as many fans as I can fit in there (2 oscillators and 2 exhaust). I suppose the main problem is that I'm venting into my bedroom. I live in an apartment building, so venting outside is out of the question. My bedroom, even before the grow closet, has always run a bit hotter than the rest of the house because I have sliding glass doors that face the sun all day. I tried covering them with black visqueen (in addition to the verticals that are already there) to block out the sun from heating my room, but it made, literally, no difference in the temp.
I know the current temps don't sound too bad, but during summer, it was averaging 95f in there during the day. Now that it's "winter" it's cooled down a little. Since my closet is right on the other side of the angled roof, the temp inside the closet seems to stay consistent with the temp outside. Let's just say, my "winter" is usually in the mid-80s. We're lucky if it gets lower than 75 for more than 2 weeks. During summer it can get as hot as 110f here. I lost a whole crop last summer, minus one very strong mama who seemed to have permanent damage from the heat.
So, yeah, everything's OK for now, but come summer, I'm thinking I can expect more marijuana homicide. Right now, I have White Satins, which I've read can take the heat very well. But I've recently been given some White Russian seeds and have some Jedi on the way, and I don't know how well those will fare.
About raising the lights; I did have the lights farther from the plants, but I was getting some bad stretching. So I've just adjusted so the plants which are now about 8-10" from the lights. The heat damage to the clones happened when they were still a good 24" from the light (and they're under the 250w)
So, what size block of ice are we talking about?
ETA: Without actually measuring right now, I can tell you the closet in question is about 9'L x 4'W x 7'H (Ahhh, I love the closet space here!) And I will definitely take some pix when the lights come back on to help illustrate the situation.