Before you go to the trouble, have you made sure all your vents/ducts are fully clear and you're pushing a good amount of air?
There are many threads here of folks complaining they aren't getting heat from their vents. Turns out their vents are twisted or crimped.
1988 Coleman Sequoia - popup (1987-2009)
2012 Roo19 - hybid (2012-2015)
2016 Mini Lite 2503S - tt (2015 - ???)
2011 Traverse LT, 3.6L, FWD
2009 Silverado Ext Cab, 5.3L, 4x4, 3.73
2016 Silverado 2500HD Dbl Cab, 6.0L 4x4, 4.10