Topband: EWEs, 2-in-line or side-by-side

[Josep]

I have a four-directions switchable EWE right now, but have been considering trying an array of them. I would like to hear comments about people that has tryed 2 in line or side-by-side. Is it critical if they are not at the same terrain level (>2m)..? In a past QST article by WA2WVL, to phase them it says you need to run the same length of coaxial cable to a common center connection, (T connector ?), and from there to RCVR, thats all you need to get them running..?
Thank you,

Josep
EA6BF