Minor installation question

[Havok.]

Question here is, to play EB under 1.5 as usual, am I safe enough installing it as is, or would I be much safer uninstalling BI and RTW and starting clean? Will installing BI have put any 1.6 stuff into my 1.5 install?
This is curious, I just ran RTW, and it says it's version 1.3. Did installing BI remove the 1.5 patch?

Try installing a separate 1.5 patch for the rome.exe, i'm sure it will work
rtw patch 1.5