Question about an SBR AR-15 kit

[RCS]

Total noob question, but I can't help but ask. In the back of my mind I've been wanting an SBR'd AR for quite some time, and I finally convinced myself it's my next toy (after a LR308), so I need to ask you guys:

Would this be legal to own (without assembling it, of course) with a seperately-placed (my dad's house) lower reciever without the tax stamp?

http://www.gunbroker.com/Auction/Vie...Item=195435917

I don't know thing one about tax stamps, so any additional info I could come back to when I decide to pick this up would be greatly appreciated. (Like do I have to engrave the lower, do I hate to include serial #'s when I send out the tax stamp, etc.)