92 Exhaust cam help

[SilviaS14KA24DE]

Ok, I've searched, and have been confused. I just picked up a 92 (or 93) exhaust cam from the junkyard for hecka cheap. Now the questions:

Do I need to machine the cams? Or can I leave them as they are and install them?

and

How do I install this myself? I read that you have to line the sprocket with the timing chain (mark it, if that eases any confusion).

also

I bought the cam with the s13 sprocket attatched to it (we didn't have a big enough socket to remove it). Can I just leave it on and it will work the the s14 ka? Or do I remove it.

Any clear installation help would be good if someone can. I'm nub that this.

[SilviaS14KA24DE]

buump

[sheadee240]

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