It doesn't actually look like they reversed the taper at all, I think they drilled it out and inserted a bolt which passes thru a spherical joint which has been inserted into the lower control arm... no ball joint boot, and the distance from pivot to mount with a ball joint tapered pin is much greater... picture doesn't show the underside on the ball joint, but my guess would be you'd see the head of a bolt on the underside of the arm.
The trouble with a straight flip, is that the pin normally inserts from the top at an angle, if you flip the ball joint upside down (which on a 128 sedan or a ritmo is possible due to the arms design) you would effectively pull the bottom of the hub inwards (creating positive camber and reducing the SIA)
Thats why the inner point is adjustable for length, to firstly correct for this difference, and secondly it would allow geometry changes to alter things lke the scrub radius when larger wheels / tyres are used.
On a 128 coupe or an X19, flpping the arm isn't possible because of it's design being a left / right specific am. So my lemons racer I've replaced the ball joint pin with a spherical joint and a bolt, repositioned to under the arm, the bits will be here in about a week from the UK and I'll show you how it's done, but this is an artists impression. Pulling the lower pivot point inwards by 10/12 mm which this will do is no issue in my setup as I've increase the SIA considerably by repositioning the upper pivot inwards, so the fact that it pulls some negative camber out is beneficial for me.
at the rear a similar change, but I dont think it will fit into 13" wheels as the lower arm / ball joint just clears my 14's
Fiat part numbers that begin with "702" are generally from Abarth works, not available thru Fiat dealers generally....it wont even appear in the dealer price lists from the 1980's.
SteveC
SteveC