How to use RH when documenting duplicate products

Using RH11 generating WebHelp.

My company is producing a new version of a product. They want to use the same name as the original. They are also keeping the original product (so yes, we will have ProductX and ProductX.)

1. I realize that I can't have two topics called ProductX in RH. Any suggestions besides coming up with a different name for the new product, like ProductX V2?

2. Can I use conditional build tags to populate RH with either the original help topic or the new help topic, depending on the version of ProductX that the client has? I'm trying to avoid having two help systems to maintain.

I apologize if I am not being clear. I do not have any advanced skills in RH so I am unclear how to go about solving these problems.Thanks for any advice.