With the B310 Sunny, there is part of the pedal box right where you want the clutch master cylinder to come through the fire wall. The easiest way is to get a manual pedal box from an A10 Violet/Stanza/510, which was heralded as the rebirth of the Datsun 1600. It's not quite a bolt in, as the 2 mounting studs for the clutch master cylinder are about 10mm towards the transmission tunnel & interfere with the speedo cable. All you have to do is drill the 2 holes for the studs & 1 for the master cylinder, the body of the pedal box blocks off the two old holes, & the rubber grommet around the speedo cable simply needs notching. Another way is to mount the master cylinder inside the cabin, on top of the pedal box. There's plenty of room in there, you just have to fabricate mounts & a pivot off the existing clutch pedal. Maybe a left hand drive pedal box could be used in the car, as they were all hydraulic clutch. Somebody on the European continent might be able to supply one, maybe from Portugal.
It's then a case of making the hard line from the master cylinder to the flexible hose that comes out of the slave cylinder. Once you've got the master cylinder in, & have a fair idea where you're going to join the hard line to the slave cylinder, get some welding wire & create the shape you want, then go to a brake company & get them to use that as a template for the hard line. Don't forget there has to be a mounting point where the 2 lines meet, this is usually a tab of metal at 90 degrees to the chassis rail that has lugs to hold the end of the flexible hose.
I hope I've helped, with the conversion I did, (L18,A63 g/box) I used a Mitsubishi master cylinder from a Cordia Turbo, which has a flexible line all the way & a bango style fitting at the master cylinder end. I got a local Hydraulic hose company to make up the hose, using ends I supplied. I'll definitely be doing the same when I put the SR20de,71b g/box in the next one, I'll just use braided line.