BSCowboy - I searched in my usual places, but did not find a description of your bolt #106329. However, here are some sources for future fastener searches ...

PARTS NUMBER SOURCES:

Descriptions of fastener numbers is pretty frustrating. I don't know of a totally accurate source of descriptions for GM numbers. I use a number of sources and searches to find info. If all else fails - as Achipmunk says, use what fits.

Many of the GM part numbers are industry standard numbers. Websites of hardware suppliers to the Government often show the description. I sometimes find info on the item by doing a Google search of the part number and a brief description such as "bolt 3701135" for the outer bolts in the front engine mount of my '54 3100. Or, "washer 352282" for the middle washer on my '54 front engine mount.
Here is one of the "washer 352282" hits that gave me thickness info available nowhere else ...
http://www.wbparts.com/rfq/5310-00-447-2493.html
and info on "washer 365685", the end washer on the front motor mount at the same site ...
http://www.wbparts.com/nsndetail.cfm?NIIN=004496420&pn=365685
Try the site to search for other part numbers. I found your #106329 mentioned on a gov site as part of a Chevrolet Transmission Assembly, but no description of the bolt.

BillyBob - may not be 100% accurate for concours judging, but this list may be the best source available and they have been provent to work.
http://www.laroke.com/larryk4674/2005/bbpartshp2.htm

Here is a community Google Docs spreadsheet that I started (and did not complete) based data supplied by Larry Kephart and BillyBob and on info in the Factory Assembly Manual. I believe that you have to sign up for Google Docs (free) to view it.
https://docs.google.com/spreadsheet/ccc?key=0AuWjRxoWPR74dFlPNWFzWUJoMFRnMXNiMWhHMmI4cVE#gid=0

SOME OTHER LISTS:

Stock Corvair Group
http://stock.corvair.org/wpmu/blog/2011/11/gm-fasteners-table/

Plymouth: The First Decade
http://www.ply33.com/parts/group18

GMPartsWiki is also a good source. It has been posted by Stovebolters before.
http://www.gmpartswiki.com/query

The MPC has standard hardware items, but only a few of the numbers match the numbers in the Assembly Manual.
> Standard Parts Listing 1929 - 1954
8.899
p.473 - p.482
http://chevy.oldcarmanualproject.com/1929_54chevyparts/08/473.HTM
> Standard Parts Listing 1929 - 1957
8.899
p.641 - p.652
http://chevy.oldcarmanualproject.com/1929_57chevyparts/57cmpc0641.htm
Also, illustration indexes in the Master parts Catalogs ...
> Illustration Index 1929 - 1954 MPC
http://chevy.oldcarmanualproject.com/1929_54chevyparts/info/039.HTM
> Illustration Index 1929 - 1957 MPC
Primarily '49 - '57
http://chevy.oldcarmanualproject.com/1929_57chevyparts/57cmpc0055.htm

The hardware item and dimentions are sometimes shown in the MPC section for the item that it attaches to, such as this listing for Group #0.002.
http://chevy.oldcarmanualproject.com/1929_54chevyparts/00/093.HTM

Here are abbreviations used in the MPC that may help define the type of fastner
http://chevy.oldcarmanualproject.com/1929_54chevyparts/info/005.HTM

Please post the source if you find an answer to your quest.

- Lonnie
My '54 3104
Photos that I have shared on Stovebolt via PhotoBucket are no longer available. Please contact me if you want a photo from an old post.
lonniecook [at] aol [dot] com. I sold my '54 3104 12/12/2017, but I still visit Stovebolt.

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