A silly 8E question, appreciate some help please.

How does one resolve wound allocation from an attack dealing multiple wounds (say Lascannon) against a multiwound model?

Say I have 5 Lascannons successfully hitting and wounding a unit of 4 Custodes.

Is it:

• Custodes player allocate 1 wound to each of his Custodes, with 1 Custodes taking 2 wounds
• Custodes take their saves
• Custodes that failed saves take the wound multiplier.

If this is true then won't there be a lot of bookeeping and allow players to play pseudo wound-musical chairs?

Thanks a lot fellas! Hows the 8E gaming so far? I am having a blast!