I was told by technician I need to renew mine. Has anyone here done this job? I have 79 280ZX manual steering.

 

Replaced them on my original '86NA. Techie was a front end alignment pro, lifted the car, grabbed the tire at 9 and 3 oclock and could wobble it. Not supposed to wobble. I took the opportunity to rebuild the whole steering rack, ball joints, bushings, etc. I figured since I wore it out, I should fix it. Included poly bushings. You can check out the parts numbers on your XenonS130 fiche and start with those to find replacements. Otherwise there are a bunch of pretty cheap kits out there that can be adapted to fit, or so they claim. It cost me a little more to do the whole set-up but it saves on tire wear. Getting my original factory Z steering back was worth it. Rock solid straight ahead on any road surface. Car is still knocking my socks off after all these years!

 

Can the inners be done on car or should I remove rack?

 

On a Z31, you can just do the tie rods. Check your service manual and parts fiche for the S130/280ZX. I bet you can tell that from the diagrams.