Arachnarok Spider - Flinger Conversion

I've been slowly moving forward with building my two spiders and decided to make both of them the basic howdah build. So what to do with the spare parts and is it possible to make them slightly modular?

Arachnarok Spiders

I always try to make duplicate models look different, so with the Spiders I thought the easiest way would be to base them differently, of course it ended up a bit harder than I thought it would.