If you have an older machine, you are probably OK with all models,whether bridge or horizontal.

Manual machines are easy - you just need to read the scales. I know of upgrades on the Micropak21 and the MAG series of controllers. Were there any others?

DCC machines are also not too difficult. I know of upgrades on the CMMC1, CMMC3, and CMMC3s controllers. The big problem would be if you have a CMMC1, since spare parts for this are all but non-existent. Two or three years ago, Mitutoyo had only three motherboard sets left, and Ford bought 2 of them! The CMMC3 and CMMC3s are no brainers!

The newer Bright series currently requires a controller retrofit.