Can you not get your heater box out with the cage in?
Found them on Genright's Site, theirs only use one bolt? and they are a good bit more than the TG version. I'm not sure what the advantage would be.
pretty sure they use two bolts, one on each side like the synergy/poly ones. I ordered some not long go from poly. Everyone seems proud of them.
Matt at Gr8tops used to have some for factory cages he used on TJU rear cages. Those are probably too big though.