Rotten Rexx/Dieceratops Cut/Assembly!!!
Alright, guys! At this current moment in time, all I can provide is a few images and limited advice on how to assemble these garage kits, namely the legs of the body! First and foremost, have gloves. You will need to heat up the entire body of the Rexx/'Tops to the point where it wiggles around, somewhat like rubber. This is to ensure the ability to stretch the body's leg hole opening over the joint of the actual leg, which is to *not* be heated! Keep the legs(and arms/head) cool!
Firstly, while these kits are cut, there is a certain degree of DIY that may or may not come with them. As a measure of ensuring your joints will fit tightly, and your Rexx/'Tops will not fall face first due to loose joints, there should be one to two millimeters of vinyl "lip" extending from the actual cut line. Heat vinyl *only slightly* to help ease of cutting! *CAREFULLY and SLOWLY* cut away from yourself when/if removing any excess vinyl!
Bearing in mind, that vinyl lip, there is a specific divot or dip between the leg and joint where it should rest when the leg is inserted into the body. This is where it gets tricky, and where you'll have to finagle and stretch the lip over and into this divot. I'll attempt to make a video for this at some point, but it's difficult due to managing the stretching with one hand inside the body.
As best as I can describe, one hand will be holding the leg into the body, and the other hand will be inside the body, thumb sticking out of the arm hole, with the other four fingers pressed, pinching and pushing the vinyl lip over and into this divot. I do apologize for this confusing description, but hopefully a video managing an example will come soon!
You can take a light of some sort(flashlight or phone) and see the inside of the body to check the joints. If it looks like the above image, your legs will eventually pop out the more they're rotated. It's simply resting in the body, and not "locked" and secured in the previously pictured divot.
If assembled and placed properly, your inner joint with look like this. You will see that the vinyl lip is sandwiched between the leg and the rounded joint. To reassure yourself that this is secured properly, give the legs a few rotations to the left and right.