quote from maintenance manual: "data transferring error took place in MDI & CRT".
This would be related to the MDI board, cable or the motherboard, not the CRT.
mem. is correct did u swap the connection bds ( I/O ) boards. look at the jumpers.
also the string that goes from DIo out of the bottom of the M/B to first i/o to second i/o and on to the mdi pcb ( cables)