Small update.
Best glue is super glue for gluing latex. I use ZAP A GAP Medium CA+ and gluing only in few point to use latex between rest of the connection line between parts. Latex is the best glue for latex BUT you have to clean latex before gluing and this is very tricky. To clean latex you have to use Citric Acid mixed with water. It opens the pores of latex making it fantastic to paint and glue but not for super glue. Why? Because you use same mixture to clean Super Glue from materials and hands and I was surprised when my glue was like water. No worries , because you have to clean this area with fresh water and just paint with fresh latex and leave until will be dry . Then you can use again super glue .
I paid for one month for Stan Winston School but they deleted all content about predator costumes and have only one episode about foam latex project similar to mine. I do not have resources , dozens people and production line like them so it is stupid to try doing something similar.
I am gluing second arm now and maybe in next few days will have more photos.