I have two goblin welders in play, a Spine of Ish Sah and a Krark-Clan Ironworks. Assuming the other target for goblin welder is legal. I am trying to figure out where the spine end up and if i can destroy more than one permanent with it.
Spine of Ish Sah
When Spine of Ish Sah enters the battlefield, destroy target permanent.
When Spine of Ish Sah is put into a graveyard from the battlefield, return Spine of Ish Sah to its owner's hand.
Goblin welder

Choose target artifact a player controls and target artifact card in that player's graveyard. If both targets are still legal as this ability resolves, that player simultaneously sacrifices the artifact and returns the artifact card to the battlefield.
is this how the stack would go if weld out spine once?
[destroy target permanent < return spine to hand]
Now can i respond to the return to hand trigger with the second welder to return it to play?
stack:
[destroy target permanent < return spine to hand < weld back into play with the second welder< sac to Krark-Clan Ironworks to place it in the gy< destroy peremanent< return to hand]