Can the Integral rails be fitted to narrower cabinets?



I’m trying to figure out how hard it would be to adapt the INTEGRAL  rail fittings (link) to work with two 40cm wide doors instead of the two 60cm wide ones. My FAKTUM cabinets will be 80cm wide but I would really need sliding doors.

Would it be just a matter of cutting down the horizontal aluminium pieces from 120cm to 80cm and drilling new holes in them? Or would it be far more complicated than that?

I’ve been studying the instructions but I’m still unsure if this is an option. Any suggestion will be greatly appreciated, particularly from people familiar with the INTEGRAL rail or any similar IKEA rail system.

Thank you all in advance!