Known CPU board ROM versions:

    * 3A - indicates a screen modification kit has been installed for use with MacWorks.
           Also, the Lisa Video state ROM has been changed for the new video timing,
           and (usually) a transformer has been installed between the video board and the CRT.
           3A ROMs will not work with Lisa Office System, Workshop, Xenix, etc. Part Number: 341-0346A and 341-0347A
    * H - the latest ROM for Lisa Office System. Also compatible with MacWorks and Xenix. Part Number: 341-0175H and 341-0176H
    * G - Very Rare - development only? Part Number: 341-0175G and 341-0176G
    * F - Early Lisa 2 ROM for Lisa Office System. Also compatible with MacWorks and Xenix. 341-0175F and 341-0176F
    * E - Very rare - development only Part Number: 341-0175E and 341-0176E
    * D - somewhat common, might work with both 3.5" floppy as well as Twiggies Part Number: 341-0175D and 341-0176D
    * C - Lisa 1 ROM (rare) Part Number: 341-0175C and 341-0176C
    * B - Lisa 1 ROM (very rare) - development only? Part Number: 341-0175B and 341-0176B
    * A - Lisa 1 ROM (very rare) - development only? Part Number: 341-0175A and 341-0176A

Known I/O board ROM versions:

    * A8 - Lisa 2 Part Number: 341-0290B
    * 88 - Lisa 2/10 Part Number: 341-0261D
    * 40 - Lisa 1 - for use with Twiggies (very rare) Part Number: 341-0138E, 341-0138F
    
