Butyl rubber glue, pretty easy to find a roll on ebay. But your existing glue should be enough (stick it back in the oven to warm them up and squeeze the lens and housing together).
You can do it in a day.
You need to calm down, note the " " BTW my HICAS is trying to kill me at 1/10 driving.
Also, I think Shuto Kousoku 2 came out around 1990, no idea if they had HICAS delete kits back then.
Lots of people have fit the R33 GT-R wheels with just a guard roll. I can't remember which tyre size, but you can run 235-255 depending on your setup.
As for distances, measure yourself? It'll probably be quicker.
You didn't state which wheels you are putting on.
You want something with 12x1.25mm "Nissan" thread and in steel.
http://www.ebay.com.au/itm/BLACK-STEEL-WHEEL-NUTS-x24-ROTA-M12x1-25mm-/161234975813
http://www.ebay.com.au/itm/NEO-CHROME-TITANIUM-STEEL-TUNER-WHEEL-NUTS-x20-ROTA-M12x1-25mm-/151285857731
I have a packet of these at home doing nothing:
http://www.ebay.com.au/itm/BLUE-STEEL-TUNER-WHEEL-NUTS-x20-ROTA-M12x1-25mm-/161233337453
One fell out of the packet though (19 left, packet came slashed). You want to run lock nuts so they'll be fine