New ATV and HRC power up kit?

So, I'm looking at getting a new atv. It's a 2013/14 Honda TRX450r. I'm only having one issue. I want to get the HRC power-up kit, but I have no idea how to install it. And if I let my uncle work on it up in his shop, I won't get it back for a year. So really I have two questions. 1. Can I buy the HRC power up kit by itself? 2. Should I get a new or used TRX450r?

Why not ride one first before deciding to tear into the engine?

Or buy something that suits your needs out of the box?