I did this a short while ago. I found some of the assault intercessor sprues and decided to get them all built in a batch. We do it in painting, why not building too?
Step 1: lay out the bases

Step 2: snip all the parts out and arrange them on their bases in neat piles.

Step 3: get rid of the flash and mold-lines and glue them all together.

Step 4: find that one mental guy…

Step 5: undercoat!

Looks like I’m going to be painted some marines pretty soon!