334.80 says type NM (romex) shall have conductors rated 90 degrees C

So...the romex used in the 80's had conductors rated 60 degrees C

So... in this kitchen remodel I'm doing (the one we already determined that I have to replace the type SE range line), can I use the old branch circuit romex feeding the kitchen, which has conductors rated 60 degrees C, bring them into a juction box and extend new 90 degree C romex to the new plug locations, dishwasher, micro, etc???

The panel is located in a plastered garage and it will be difficult to access.

Or would Mass Rule 3 apply here also?

shortcircuit