Try and find a model number on the side of the box and do a google search.
Or take a photo then do an image search to try to match it up.
Do you know who did the conversion?

This should help-

180SX CA18 Workshop Manual

Download this and all your dreams will come true! Sort of....
It's safe, I did a trial download. Just a PDF document.

That's a pisser Chris, I scanned from top to bottom in 30 secs and deemed it too hard!
He's right Mik, you make decisions, as long as that decision doesn't require you spending any/much money!
You're the cover girl for The Frugal Fairy Magazine!

It's just coincidence that the clutch is gone after the master cylinder. Do you know if the clutch was replaced when the engine was installed? It could be 150000kms old for all you know.
Ring ABS or Repco and get some prices. You will need a full clutch kit.
Make sure you know the model of the car that the engine came out of and the year it was manufactured.
It should be only a few hundred for parts.
You can DIY if you know how to pull out a tranny. The main thing you might have trouble with is aligning the clutch upon reassembly. It's pretty cheap and easy to find a clutch aligning tool. Don't try without one as it can make life very difficult if it isn't properly aligned.
It's not a hard job, just time consuming and fiddly to do on the ground. The bigger the transmission the harder the job.
Good luck!

Ok, last price, maybe a bump or two in it though.
If it doesn't go at this, it's a loooooong term project!

Now $1000

You're right Don, it does.
My bad.

That's awesome!
I need one of those in my bedroom!

The fluid won't drop much when you push the pedal down. As the piston moves forward in the bore it covers the hole that goes to the reservoir. It might fluctuate a tiny bit but not much.
If it looks like the clutch fork is trvelling it's full travel forwards AND back then it's looking more and more like a clutch plate issue.

The fluid level should drop. As the clutch plate wears the slave cylinder moves further forward in its bore. this obviously creates a cavity behind it that needs to be replaced by fluid, hence lowering the level.
Get under the car and get someone to activate the pedal. You may be able to see something funny while you're under there.
Also check the rubber boot that the clutch fork goes through into the box, just to make sure it isn't jamming the clutch forks travel.
If all that looks ok, if the clutch slave is easily accessible, whip it off and pull it apart just to confirm everything is ok. There's a possibility that the piston could be stuck in the bore, holding pressure on.
While the slave is out and the fork boot off, see if you can use a folding telescopic mirror and torch (shine torch onto mirror to reflect into the box) to see if you can see the clutch diaphragm fingers.
Other than that, without being there, I can't think of anything else!

Slightly off topic but....

I bleed outta my vijay jay too sometimes. I told a customer the other day I was disappointed with their behaviour. He tore me a new one so I stopped bleeding and crawled into a hole. I won't contact customers when I'm tired and emotional again!
Back on topic now!