Adding Vista to XP ,W7.


I curently have Windows XP and W7 on two seperate hardrives,using Easy BCD ,
I would like to purchase another hardrive and add Vista ,how dificult would this be,
i am a newbie,or maybe i should not even try to this maybe screw something up again.Thank You EasyBCD your the best.
No problem.
Disconnect the present HDDs temporarily and do a clean install of Vista on the new HDD.
When it's up and running to your satisfaction, just reconnect the other HDDs, change the BIOS back to boot from the W7 HDD (it will have switched when you booted without it), and use Easy2 to add a Vista entry to the W7 BCD.
Select the letter which W7 sees Vista as, not C which Vista calls itself. (you can set the letter to whatever you'd prefer W7 to call Vista (V for example) in Disk Management.