Woah, you're gonna rebuild it just because you got a little bit of lifter noise and a cyl 3 misfire? Talk about jumping the gun. And 145K isn't high for these motors so I highly doubt a "rebuild" is worth it. Have you even tried troubleshooting these issues? Bad plug wire? Bad plug? Bad Coil?
It is expensive to rebuild these motors correctly and have them last. You have to have the block align bored and the entire bottom end checked out or it will most likely grenade on you shortly after reassembly. A machine shop assembling your entire bottom end would be best.
Beyond that, I would go w/ a low mileage longblock and just swap over your stuff and call it done. Way cheaper and you know the bottom end is good.
And before I forget, are you COMPLETELY stock right now, or did you drop a pulley size or something? Are you running premium gas in it?
