Keep it really simple and try just pilsner malt, Saaz or Sterling hops, a bunch of water, and Czech yeast. You might want to prepare your water from distilled water and brewing salts too. Can you control your fermentation temperature too? I think that's going to be the most critical part to making a really good pils.
I too want to make an Imperial Pils, and was thinking I'd shoot for an OG at around 1.065 - Not too high, but a lot higher than normal Pils.
Keep us posted!