If you do a search on ICW for "I90", you will find plenty of Iida made AR models with a 1989 serial number.
As you will find a few Artfield guitars from 1988 if you search for "I80", because these two series of Ibanez guitars WERE made at one and the same factory.
I've made some minor edits to this page to address the concerns you've presented. I've changed "produced by Hoshino" to "produced for Hoshino" and have altered "Artist production resumed in 1990" to "The Artist line was brought back for 1990".
Please let me know if these edits provide sufficient clarity on this topic. If not, please feel free to edit the page yourself.
As far as the "I90" and "I80" discussion, I'm not sure what you want me to do with that. If you see anything on the wiki pertaining to those SNs that looks incorrect, please point out the specific passage.
I90xxxx serial numbers that appeared on AR and AFD models were used to express that a guitar was made in 1989, not in 1990.
Guitars from 1990 had a I00xxxx serial number.
The second digit (a zero) was just a placeholder.
The only digit that counts is the first one.
I80xxxx = Iida 1988
I90xxxx = Iida 1989
I00xxxx = Iida 1990
I10xxxx = Iida 1991
I20xxxx = Iida 1992
That is how the serial numbering system after 1986/'87 worked.
That was the era that it was necessary to use a LETTER for the distinctive plants who actually made the electric guitars, after Fuji Gen stopped being the sole supplier.
From 1987 on they used:
F for Fuji Gen
H for Haruo Terada
I for Iida
Y for Yoojin (Korea)
A search for the character combination "I90" on the Ibanez Collectors World forum proves that several AR300 and other AR guitars were actually MADE in 1989.
That's why they were already on the USA pricelist of January 1990, which can be found on []
You cannot put them on the January pricelist, if you haven't got any guitars yet.
A search for "I80" only got me one Artfield guitar so far... so there is indeed no proof of the existance of any AR guitar that was made in 1988.
I am in the posession of an green original 1988 pricelist with model drawings of the Dutch distributor Serlui (nowadays Hoshino Benelux / Hoshino.eu), which is somewhere in a box in my garage since I moved.
I know that several Artstar models (ex semi-hollow and hollowbody Artists) are on that list, some made by Terada, some by Yoojin.
Artfields were on it, that I know for sure too.
I'll just have to check, whether there are any AR models already on that list.
I've removed the section from the serial numbers article that detailed SNs from Ida Gakki with a 2-digit year code (i.e. IYYXXXX). I've concluded that no such numbering scheme existed on the logic that if it had SNs for guitars produced in 1990 (if they used a 2-digit year) would share the same SN configuration for those produced in 1989 (which had a 1-digit year code).
Let me know if you think these assumptions are incorrect.
Do you have an idea of over what period Ida produced guitars for Hoshino?
Also, do you know if the company name is Ida Gakki (one I) or Iida Gakki (two Is)? I've seen it both ways (and even, probably spuriously, as Lida in a couple of cases). I'm leaning toward Iida, but can't find a definitive source.
Update: After a bit more research, I've settled on Iida and have created an article: Iida Gakki. I'd appreciate if you'd give it a quick read and share your feedback.
All of the 1990–1992 Artist model articles have been updated to reflect they were produced by Iida. Are there any other models that you are aware (among those within the current scope of the wiki) that are produced by Iida?