Hi, you need to replace the P1, V1, C1, C2 chips with 4 x M27C800 eproms, the S1 chip with a M27C1000 eprom and the M1 chip with a M27C1001 eprom. The eproms can be programmed with a regular eprom programmer which supports 42 pins and the given eprom type (my programmer is a WELLON VP 280B).
I...