[Z71GMCSierra]

OK, I own a 03 GMC Sierra Z71. Today, I went and ordered the Ford Keys(00 Ford F-150 keys). Then I go see how much it would be to install the keys and blocks. This is a stock truck(FYI). And, the guy told me that it would be $100 to install the blocks and the keys AND he said that to put blocks in the back, he would have to undo the back shocks to put blocks in?? Never heard of this before. He also told me that my shocks wouldn't hook back up with the 2" block in the rear. So, I'm turning to you for advice. I am going to get new shocks when I get the money. But, could I do this and get away with it for a couple of weeks before I get my new shocks? The ride is not that important to me. I just want a way to fit 33's on 16x8's. And, of course, my dad won't let me lift it. So this is my only option without him noticing. So here are my questions:
1. Can I do this install front and rear without replacing my shocks?
2. Is installing the blocks in the back really that difficult?
3. Is the torsion key swap really difficult to do? I think I can do this, but I just don't want to break anything :crazyi:

Thanks, for your help. Please be patient with me :-D