The residuals are correlated both in column (兿c = 0.683) and row directions (兿r = 0.458) with the common residual variance of 0.33754. So, residuals on plots separated by two rows and three columns would have a covariance of ..!
!..!
!..!
! = (0.459!)(0.684!)38754.3 = 3819.9.