I looked at the article, and its references to "L" and "R" are misleading. The amps are monoblocks, each of which of course is connected to just one speaker. Each amp has two pairs of output terminals, which are paralleled (i.e., the two + terminals are connected together within the amp, and the two - terminals are connected together within the amp). "L" and "R" apparently just refer to the physical position of those terminals on the rear of the amp, not to the left and right channels. Since the terminals are paralleled it won’t make much if any difference which terminal is used for which wire, assuming + and - polarities are handled correctly.
Regards,
-- Al