your questioning of installing it on the rear, did make me go back and look into this particular solenoid (the b&m). I typically install these on the front... I have installed one on the rear in the past, but it was a different brand, couldnt remember which brand or why at the time i ordered it...Line lock on the rear ?
reading the instructions on the valve, made it seem as if you may be able to pump pressure passed the solenoid after energizing it... so just to be sure, i re-tested it (using a power probe)... the first time i tested it, i pressed the button and only hit the brake one time . it seemed to work, if you just hit the button, press the brake one time. but if you were to let up a little pressure and push the brake again, or pump the brake, it does appear to increase in pressure and send all the pressure through the solenoid... which is great for the front brake setup... not so much for how i have it here... could prob reverse it (so the check valve direction would be from back to front).. but i dont like that.
i went ahead and ordered the moroso valve (44050)... and verified that it will work as intended (blocks pressure both ways)... and will test again, once i install it...
long story short, some people are hesitant to question/criticize something someone else is doing. but i would like to thank you for doing so... i would have eventually caught it, but... your question made me re visit it now to make sure it would work as intended... and save me extra headache/irritation