Shimano MTB front mechs are tricky to pair up with road STI due to reach/ cable pull/ leverage but there are plenty of Shimano Road triple front mechs that are designed to run all sorts of chainring sizes
Shimano MTB rear mechs from 1987 to the last of the 9spd run perfectly with any Shimano Road STI up to 10spd (using 10spd chains) without any modifications
I've been using Dura Ace 10spd bar-cons with 1987 MT-60 f&r mechs without issue, they indexed really well
If running a 9spd front mech, use a 9spd chain as the cages are narrow - 8spd chains will rub.
9spd chains run very well on 7/8spd cassettes.
I'm also using Mountain LX f&r mechs with 9spd bar-cons and a 9spd chain/ cassette. Its all indexed nicely