Based around a 3×8 set up with drop bars and shimano sti shifters, would this work:
triple 8 speed road sti shifters
8 speed triple road front mech
8 speed triple mtb chainset 22/32/42
8 speed mtb cassette 11-32
8 speed long cage mtb rear mech
I feel it should but it would be good to hear from those more experienced than me.
Thanks.

anyone?

Sounds fine to me. You’ll be needing a chain too. And brakes.

The only problem is getting 8 speed STI’s even Sora is now 9 speed, if looking at new, it will be NOS parts which could be hard to find.

If you went 9 speed, parts are much easier to find.

Thanks, I have a chain in mind 🙂

I have already got the shifters, chain and cassette in the parts bin hence the question.

Cheers.

Just get the chain line right with the correct BB length, and you should be good to go.

Take it that this is for a tourer?

Cool. More a monster cross 29er than a tourer.