Posted for randy snarr <randylsnarr@yahoo.com>:

 Gary/Chris
 On my receipt is shows part # R-640788
 On comments it states 2399740101 108AA19-ALBSP-3VT
 R/V=1400 UP,800 DOWN
 OVERHAULED AND UPDATED TO BACK PRESSURE CIRCUIT
 $125 4-23-02
 Looks like they did do the back pressure circuit mod.
 How do I verify my back pressure mod was actually
 done?
 
 Randy.