3.6kg LME and 0.3kg DME in 23l will give you about 5.1%. If you want more than that, you can add 0.5 kg sugar to IPA safely enough, it's supposed to be relatively light bodied and dry. That would get you up to 6.1%.
Hop-wise, 10g for 10 minutes will add very little bitterness, about 2 IBU. 30g@7%AA for an hour will add 20 IBU. Boil the hops in a lot of water, a gallon at least. It's hard to guess how bitter your kit is to start with, but if you want to make a proper IPA, an extra 20 IBU should be fine, White Shield is about 55 IBU.
40g dry hop is plenty, possibly too much if it's a modern hybrid.
http://www.buildabeer.org/beercalc.htm