How Can I uninstall the SAM products?

Have you installed it in conjunction with other SolarWinds modules or is it a standalone SAM installation ?

cheryl1 has pointed you in the right direction, go through that link.

But with the kind of experience I have with a multi module setup, its not always easy to uninstall SolarWinds modules, its best for you to raise a SolarWinds support case. If I am not wrong for some customers they did provide custom uninstall scripts to uninstall modules, but then it again depends on case to case basis, this is not something that SolarWinds support does on a regular basis.

But end of the day I am not very confident or comfortable in stating it will be a clean uninstall.

Correct. A support ticket is probably a good idea if you're not completely sure. I do know in recent years we've released several improvements to make an uninstall easier but sometimes as with uninstalling any complex software, there are some cleanup steps that have to be done. 

Also, and I can't stress this enough BACK UP YOUR DATABASES BEFORE PERFORMING ANY CHANGES TO YOUR INSTALLATION (yes, the all caps is intentional) 

Correct. A support ticket is probably a good idea if you're not completely sure. I do know in recent years we've released several improvements to make an uninstall easier but sometimes as with uninstalling any complex software, there are some cleanup steps that have to be done. 

Also, and I can't stress this enough BACK UP YOUR DATABASES BEFORE PERFORMING ANY CHANGES TO YOUR INSTALLATION (yes, the all caps is intentional)