I have a 2006 Express 3500 with the 6.0L Gas V8. It did not come with cruise control. I know I can buy an aftermarket kit for like $400. However, I found an OEM cruise control module (#15752335) for $60 on eBay and can get the cruise control switch / turn signal stalk for like $70 on eBay as well. Is this all I would need to install it? I asked the website that sells the aftermarket stuff and they weren't sure what the process would entail to add an original system. Thanks for any help!