'68-79 Nova rear end width is 60-1/4".
'70 C10 width will be either 62-3/8" or 63-3/4" (mid-year change). The spring pads and shock mounts are also in different places (not to mention spring-under versus spring-over); and most C10s had coil springs, not leaf springs.
So, not a straight swap or direct fit.
It could work, with some modification and different wheel offset. But is it worth it?...