Thanx for feedback, Luke - yeah, I thought you might not have to dremel a relief, as it would have been easier just resoldering (bad factory) solder-joints where the cabling are connected.
All good.
I was really hoping the old bracket was the one on the right. Means I will have to make new brackets when fitting theses to my Koolance RP-401X2 :( Ah well, bananas happens.