Not knowing what kind of dana it was and if it was OEM auto or a truck rear or one that had been moneyed with, I went with the safe response.

Axles are pretty straight forward and easy. When you remove the carrier/differential/limited slip unit it can get complex. Nothing you mentioned would be a cause to remove more than the axles. There may be those who may say it is OK to weld the tubes with the axles in, I don't. No specific reason why but it seems right to take them out when welding.

As for the inside when you remove the cover. As you said chipped gears or rust are the only things you can really see. Everything else except up down movement of the pinion would be best measured with a dial indicator.

If you haven't removed the cover I suggest you do that before you start. If the gears are rusted or chipped then I would send it out to be worked on by somebody like Dr Diff. and have the perches fixed at the same time. There are a lot of specialty tools like case spreaders and pinion depth gauges that are necessary to rebuild many rear ends and not worth the cost for only 1 rear end. IMHO.

When you tack or weld your perches make sure the angle of the perch to the pinion is correct or it reeks havoc with the driveshaft angles.

Congrats on the score.