Ok...so I blew it.
I ordered the wrong idler arm/center link to use with my original 65 manual steering box.
-The original pitman arm is the smaller 13/16
-The idler arm and center link is the larger 7/8

Question...
1. is there a pitman arm that will mount to my original manual steering box that fits the larger center link?
2. Can I drill out my pitman arm (with a taper) to fit the larger center link?

Everything is all painted up and I hope I can fix this with a simple swap vs. redoing everything...
Thanks for any help.

 

I ran into a similar issue. I swapped out my old power steering box for a quick ratio box and kept my pitman arm. I also replaced all my steering components (it was a kit that came with everything) and the center link was too big for the pitman arm. I bought this one from Holley, it's the 13/16 size, it may work for your application.
Proforged 106-10060 Proforged E-Coated Center Link (holley.com)

I also found this thread that had some useful info when I was looking around after encountering my issue.

PITMAN ARM (two hole sizes??) - PY Online Forums - Bringing the Pontiac Hobby Together (maxperformanceinc.com)

Hope that helps!

 

If I am reading the parts manual correctly, the pitman arm is 5693762. A google search turns up many

 

I've come up empty finding a pitman arm for my application...

Does anyone know in GM used a 1.5" taper per foot or a 2" taper back in the day?
1.5 inches per foot is 7.125 degrees, and 2 inches per foot is 9.462 degrees.

 

Olds made a change in mid 65 to the larger centerlink. Mid 65 thru 67 were the same. A lot of DA vendors were selling the Chevy for the Olds and it wouldn't fit. It's not just the pitman arms,it's the tie rod ends and idler arm. The bolts/studs are larger and will not fit the earlier centerlinks.I am calling from memory but that's how I think it is.

 

Thanks for the info!
I just went and rechecked…whatever I bought is working for tie rods.
Im using a right stuff disc brake conversion…and all the stuff I bought fits so far.
just the pitman arm is off.

I think I’ll be reaming out my pitman arm to the larger 7/8ths.

 

I'm following up because I've seen a few post about having to return a center link due to the switch in size in '65 noted above.
(from a smaller 13/16 to 7/8)
After some research I found that GM used a pretty standard taper on tie rods, pitman arms, idler arms etc. -
1.5" a foot or 7.15 degree
And they sell a bit called a Tie Rod Reamer that can enlarge the smaller opening to the larger one.
Took me about :20 to fix. (use lotsa oil and go slow)
It fits super snug!