Extract the folder texture.cheesy and the read me.txt to a temp folder

Copy the texture.cheesy folder to the Flight Simulator 9/Aircraft/b737-400 folder.

Open the file Flight Simulator 9/Aircraft/b737-400/aircraft.cfg with note pad.

Add the following lines to the aircraft.cfg file after the last [fltsim.x] and before [general]. Change [fltsim.x] to the next 
higher number in your list.

[fltsim.x]
title=Cheesy Air B737-400
sim=Boeing737-400
model=
panel=
sound=
texture=cheesy
kb_checklists=Boeing737-400_check
kb_reference=Boeing737-400_ref
atc_id=BR-549
atc_airline=Cheesy Air
atc_flight_number=BR549
ui_type=B737-400
ui_manufacturer=Cheesy Air
ui_variation=Boeing B737-400
description="One should hardly be surprised that the world's most prolific manufacturer of commercial aircraft is also the producer of the world's most popular jetliner. The 737 became the best-selling commercial jetliner worldwide when orders for it hit 1,831 in June 1987 (surpassing Boeing's own 727 as the previous champ). However, it wasn't always that way\s in the first few years of production, there were so few orders that Boeing considered canceling the program. They didn't, and the airplane has more than proven itself in over three decades of service."
