Epson 1500 - Manual (Page 140)

Installing the PCL5/RITech upgrade board
The PCL5/RITech upgrade board allows you to make an
Action Laser 1000 act like an Action Laser 1500.
To install the optional upgrade board, you need a cross-head
screwdriver. First you must remove the controller board.
Removing the controller board
1. Turn off the printer and unplug the power cable from the
electrical outlet.
2. Remove the optional card, cartridge, or lower paper cassette
unit, if installed.
3. Turn the printer so that its left side is facing you.
4. Disconnect all interface cables from the interface
connectors.
5-26 Options