Another idea I have had which may work better is one master PIC (primarily used for data-logging and display work) which feeds the data from the EEPROM to each of the other PIC's in turn.
Using this method I assume I could just connect all 3 PICS to the serial out side and use a different wait code for each PIC.

So the startup procedure would be more like...

Master PIC reads data from EEPROM,
PIC 1,2 and 3 in ready to receive mode.
Master PIC sends start code for PIC1, then data then end code. PIC 1 after recognising end code stores received data in an array and sends back confirm to master PIC then goes into normal operation.
Master PIC sends start code for PIC2, then data then end code. PIC 1 after recognising end code stores received data in an array and sends back confirm to master PIC then goes into normal operation.
Master PIC sends start code for PIC3, then data then end code. PIC 1 after recognising end code stores received data in an array and sends back confirm to master PIC then goes into normal operation.

Master PIC knowing all 3 PIC's have the data swtches into normal operation.

Does that sound feasable????

Leigh