Need help with CIS-urgent

[kosoh]

Running a 1982 WX urq in competitive rallies. Need to refurbish the fuel metering head/fuel distributor.
Current one on car is Bosch (Red/Blue Tag) # 0438-000-066. Stamped under that is printed # is 477449247 and printed on corner of tag# is 060.

WX parts number says 035 133 481m/0438 100 123 However above unit does work.

Questions: Will an MCI fuel metering head work on a WX?
Have another unit bosch (red/blue tag) 0438-100-060 {519 cast} on a working 1983 URQ
other numbers 060 and 26044 252

Have a third unit 0438-100-123 #458809 249 Cast 520

Which is correct unit as means difference between 450 quid and 2500 quid for refurbish versus buy.

Thanks