Grab Bar help. Oem aftermarket I.d.

I'm looking for opinions or knowledge.  I'm missing my grab bar  , AKA  stay, fender. Z1, kz900, kz1000 all share same part # 35032-022.  Yet when I try to locate one there seems to be tiny variations between them.  Most notably the curve. Some seem an actual even curve, some have a slight harsher bend in the direct center, some variations of the outside curve. 2nd the drain holes. Seems like early z1s didn't have them? The 3 , 1 in middle then others by the shock mount. Then some seem like the holes are round , some are  half round, even seen a slit. I've seen all variations listed as original.  Only reason I'm asking, I'm broken , and it'll bug me if I order the wrong one. I'd prefer a used oem because I dont want to put shiny new parts on a 49 year old dull bike. But if I do order New, from who? Cmsnl, Z1 enterprises,  Niche. Weird enough I know Niche is cheap crap, but theirs does look better than some others. 

Z1, Z1A & Z1B had an oval tail light and both the tail piece and grab rail followed that curve.
Z900A4 & A5, Z1000 A1 & A2 had a more rectangular tail light with the top edge being flat. Both the tail piece and grab rail had a shallower curve to more follow the tail light shape. 

I get all that, but the fact is they have the same part #. I know z1s rear fenders are more round,  more so the tail light.,  I get ltds have bigger seats ,so they have a different part #.  So if in 1977 I ordered a grab bar for my z1 at the parts counter, it would be the exact same one that came on a kz900, or a kz100. Right? 

Kawasaki list 73 through 77 900 as 35032-022
77 - 78 1000 as the same number. 
But there is definately two tail light / tail piece styles. 
This is a picture of a 100% unadulterated 77.  If we can find a similar pic of a genuine 73 one we can confirm either way. 
 

Well , that's definitely not the grab bar I was talking about. That's a Z900. Not a kz900. Kz900s have provisions for the turn signals in the frame as opposed to the z900 over on your side of the pond. If that also has the same part # my brain might pop.

There are some parts that once they were revised or changed, Kawasaki did not change the part number. Another example would be the front fender for LTD models - when the forks were revised around 1981 to mount the axle on the front of the forks (earlier models mount the axle at the fork bottoms) the part number was not changed. Guess how I know this?  BTW if anyone's looking for a decent LTD fender for the front mounted axle, I've got one I'll sell cheap.

Giwill, as sf4t7 stated, subtle changes were implemented along the product line of almost EVERY bit of these Z's but part number remained the same or the Newer numbering system. Concerning the grab rail, generally the waay early ones were missing the 1 or 3 weep holes and it was kinda random when they started the drillings. So any, if you can source an original 35032-022, you'll be correct. Warren showing the 35032-030, was more European. I do DIG Your inquiry!! Most persons seem to only care about shiny. Wait till You start looking for the correct winker lenses, several versions of raised font. Welcome to my world!!