I have 5 wipper arms that I thought were correct for a 66, all are trico and have the same stampings on the backside, patent 2511129.2564819, 2824639 can 1948, made in ?, TRICO;and are the brushed stainless finish. But the outer arm attachment piece on 2 of them is about 1/2" longer. Are they both correct or one or none? See photo.

The parts CD I have list the 64-66 chevelle arm as #3887573 and the 67 chevelle arm as #393832 (think a number is missing). So was there a difference from 66 to 67? Is it true the 64-65 was different and superceeded by the 66 arm? Thanks,

Jim
If I had to guess, I would say the bottom one is correct. The angle also looks wrong on the top one. The impalas and other big cars in 66/67 had arms with a different length from driver side to pass side, and the one in the top looks like it may be the shorter one of those.
As far as I can tell, 64-67 were all the same, except in 66/67 the satin finish was used to prevent glare. I have also been told the early 66's had the bottom surface polished (holdover from 64/65), but I'm not sure anyone could actually verify that 100%
In case anyone is interested, the Mustangs of those years appear to be identical to the GM arms

thanks for the info Gary, the one on the top is actually 1/2'' longer and both have exactly the same angle on the bend. and the bottom side is shinny on both. if you measure the distance the rivet piece extends, one is 6 1/2" and the other is 7". the number and patent #'s I listed I think only refered to the piece on the bottom side.

How the convertible project going? Will have to stop by in the early spring to check it out. To cold to venture out to the North Star meeting on Saturday. I sent the rear rocker molding to the guy in WI; but he hasn't got back to me on a price. He must be kind of busy.

Just looked at my originals. I vote for the top one. Mine are both 14" overall and ~7" on the extension piece. Also, the angle on the top one looks identical to mine.

Just looked at my originals. I vote for the top one. Mine are both 14" overall and ~7" on the extension piece. Also, the angle on the top one looks identical to mine.

Same as mine, around 7".

Thanks, maybe the shorter one is for a chevy II or a mustang like Gary mentioned.