12 bolt Rear End or 10 Bolt

[Snifflez]

My truck is a 67 Chevy C10. I've only had a for few months so I'm still planning out the build. The truck has a 12 bolt rear end in it with coil springs and trailing arms. My future plan is to do an LS swap. So I have a few questions, my dad says I should switch to 10 bolt because it's lighter than a 12 (my dad is old school and thinks I should just build a cruiser truck). But do think I should keep the 12 bolt for durability? If you think I should do the swap what junkyard vehicles have a 10 bolt 8.5 with trailing arms and coil spring mounts.

Any suggestions will be much appreciated