I went through all this about 10 months ago and got a lot of great replies in my thread you might find useful. Just to mention, for me the PM 42 breakout board was well worth the additional cost for the ease of wiring.
I used 2 ARI’s for my two reverse loops with the PM 42 outputs 1,2,and 3 of 4 dedicated only for short protection (output 4 not used…).