Here are my Squirrel Fans mounted in my RT-Mod Bucket. I ran that battery packs to the opposite sides of the bucket to use up the cable without needing to mod it at all. My Head is 24 3/4" and I can still get it in carefully with both fans, both battery packs, microphone & the wireless mike transmitter. I just have to take care with the mesh on the frown as I can scratch my nose on it, I've bought some nylon sewing edging that I plan to glue over the edges of the mesh to avoid this.
I used double sided tape to test mount them and once happy I ground off a couple of the mounting lugs to allow them to sit as flush as possible. Then just some hot glue on the back and push them in. The battery packs are velcro'd in to allow battery changes.
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