EQ Live & P1999 - Same PC? Issues?

[Everlove]

Been playing P99 for a good while now and enjoy it.
I've been thinking of resurrecting my old inactive live account(s) to explore some of the newer content. I had a friend set up P99 for me and when we did that we uninstalled the current EQ with all the xpacs... is it possible to reinstall it and keep it separate so that I can have both without screwing up P99? I assume it must be, but is there anything I should be really careful of etc? Any help would be great. Thanks.