Delete PT 8LE before installing PT 10 crossgrade?

I just purchased PT 11 Crossgrade from LE.

I want to install only PT 10 for now because my 2008 mac Pro won't run PT 11.

I read that I should UNINSTALL my previous version of Pro tools (PT 8 LE) before installing the new version of pro tools.

Is this true, do I have to uninstall PT 8 LE before installing PT 10, even though I have a crossgrade?