Tarantula was not a monster that was created by Tohl Narita and Ryosaku Takayama, and there seem to be no pictures available in particular to show the process of it being sculpted while little has been described about the making either.
Younger generations might find the giant spider rather cheap, the puppet itself appears to have been elaborately sculpted and the wire action performed to manipulate the puppet also seems to be excellent.
And the blinking light of its eyes that showed up against the dark background was so creepy and horrifying along with its hairy mouth moving sideways restlessly.
As the puppet is alleged to have been sculpted by the Toho Special Art staff, the giant spider’s compound eyes might possibly have been sculpted following the method applied to Mothra’s equivalents.
It is said that Mothra’s eyes were made by pressing the corner of a wooden piece onto the back side of the material (resin?) before it became hard so as to express the compound eye patterns.
Some people from the Toho Special Art Division formed their own production company called “Ex Production” afterwards as the name came from the word “expert,” and Ex Production got deeply involved in sculpting props and costumes for tokusatsu TV shows including “Kamen Rider” (they took part in the Ultra Series as well).
And it is said that the compound eyes of Kamen Rider were made in the same way as Mothra’s eyes.
Therefore, the Toho method of sculpting compound eyes might have descended from Mothra to Kamen Rider with Tarantula in between if the same method should have been applied to Tarantula.
Incidentally, I best like the early version of Kamen Rider #1 among Kamen Riders of all times (sorry for my constant irrelevance! Don’t worry, I am not going to talk about Alien Pumpkin anymore!).