adding a remote start

[yz2009]

Ive got a 2004 sierra 1500. i cannot get a gm remote start because it was not an option on my vehicle. I did some searching around and the Viper 5101 remote start with the XK01 bypass were mentioned a lot. Im thinking of going that route. From looking at the installation picture it looks like a pretty straight forward install. Do i just need to hook everything up like shown in the picture? Also will by current keyless entry button still work in addition to adding this unit? Anything else i need to worry about?