I do more service work than installs so I have a pretty elementary question regarding uncased coil installation on an upflow furnace gas furnace. I know it depends on the manufacturer, but if the furnace ships with the flanges folded up, do you guys fold the flanges back down at the perforations so that the metal coil support (field or manufacturer provided) sits right on top of the furnace, or do you leave them up and build a sheet metal support 4"-6" off the top like you would for a high temp (oil) application? I've put in more matched, cased coils and I know they have the notches on the bottom to fit with the flanges up. I had a furnace/evap today that should have been a matched, cased coil but they were out of them so they shipped an uncased. Instructions said set right on top of furnace, but those flanges were up and didn't seems very sturdy so I cut strips of sheet metal to fit under the coil (without blocking airflow), made my bends and fastened these to the flanges, then rested my coil on these and continued with the plenum. Seemed to work fine, but I'm wondering if that was more work than was needed.