Archived from a plethora of sites, primairly the now closed Ginguiser restoration crowdfund:https://readyfor.jp/projects/ginguizer-2021/announcements/189523
I missed the opportunity to help crowdfund, though I have asked the original owner of the crowdfund if I could still donate to get access to the rarer documents.
Most of the character settei included in this is also present in this gallery: /g/1436592/44f441c7a2/
Included are a few one off designs for Ginguiser, primarily on the basis that Nippon Animation had Studio Nue and Sunrise often work for them under the table (moreso Sunrise), on occasion. Studio Nue famously asked for their credits to be taken off of the design work after Kunio Okawara was forced to re-design their robots so that they'd be animation budget friendly.
With that said, its inferred that Yoshikazu Yasuhiko did a few character designs for this show, such as the original concept for Kaindark, though it too was re-done. I'm still researching this, but Yas' design can be found here on the very bottom of the page (its unmistakable): /s/afff6edea8/1436592-20
Website archive - https://retroanimechris.blogspot.com/2022/10/kazutaka-miyatake-studio-nue-chogattai.html Internet archive - https://archive.org/details/studio-nue-ginguiser MEGA archive - https://mega.nz/folder/jttT0CzY#SrudRoO2aag8YGhZMnv5gw
If you'd like to help me buy more texts to scan, I'd appreciate it! I am currently sourcing books that would be meaningful to the community at large. If you have suggestions, please contact me.: https://ko-fi.com/retroanimechris
Images 9 - 11 are originals by Motosuke Takahashi with that seems to be some assistance from Kazuo Nakamura. Page 12 is extra but shows that these designs were documented and well known at least post Ginguiser's ending.