Hmmm...
Hi Dave. This is all most strange. But it is starting to make sense to me now...
According to my official Fiat factory parts book (for '79-'81 X1/9), the part in Larry's diagram labeled as #8 is indeed 4290680 (the NLA part you found in an old MWB listing) and is called a ring. So it would appear that you are absolutely correct Dave.
I think where some of the confusion lies is that there is another rubber bushing ( #4 in Larry's diagram - Fiat # 4252182 ) on the wheel side of the bracket that is not shown in Larry's diagram (or in my parts book) . If you didn't know that the plastic ring (4290680) even existed - and it seems many here even deny its existence - then you would think that # 8 is actually the missing #4. Which it is not, if that makes any sense....
I would dare to suggest that even Chris made this error, because he says (in his listing for 4252182 ) that 4252182 replaces 4290680. Which may well be incorrect....but then again perhaps I am incorrect..
It would appear - from Dave's description and the MWB listing - that 4290680 is indeed a plastic (not rubber) ring. Even MWB wishes you luck in installing it without breaking it....
And yes Dave, it appears that none of our usual vendors seem to have any 4290680. Even a quick google search didn't really find any.
But....I did find a couple of sources that indicated that 4290680 was superceded to Fiat # 7668397, which comes up on google as for a Fiat Panda. And interestly enough, my Fiat/IAP price list from 1991 shows that 7668397 was replaced by 4290680. So it would appear they are indeed the same part.
And - wait for it - yessir - 7668397 indeed appears as an AVAILABLE part on Obert's website.
http://www.fiatplus.com/RADIUS-ARM-PLASTIC-BUSHING.html
Yipee. As a "radius arm plastic bushing for 128". But in his "unknown parts" file. And the picture looks right. And at a quite agreeable price of $1.25 each !!! Suggest you order some before Chris realizes what they actually are and prices them properly LOL !!!
And hey Chris, if you are reading this, I'd like to hear your take on all this. Please dont take any of this as being critical. And by the way, I have noticed that your website was recently revamped. Looks nice....but... I cant now seem to figure out how to tell if you actually have current stock of parts listed. The old website showed actual stock levels of every part - I cant seem to find that info on the new website. Am I missing something ? It sure would be nice to know if the part you want to order is in stock or not.
Cheers, Doug