The blower rheostat on a 93 Pontiac Grand Am is located inside the engine bay, just to the right of the blower fan housing. It is almost directly behind the trans dipstick. It isn't that hard to replace.
The Heater Blower Relay on a 1993 Ford Explorer is located in the Power Distribution Box. The PDB is in the engine compartment, mounted on a bracket attached to the right fender apron. The Heater Blower Relay is one of six relays, the first relay on the upper left.
The 1993 Pontiac Firebird or Formula with the 5.7L LT1 and 4-speed automatic has an EPA estimated fuel economy of 22-miles per gallon highway and 15 city. The optional 6-speed standard transmission offers 23 and 15 respectively.