Just found my grandfather discharge paperwork with his unit info and have also requested his records from the OPM archives. I was hoping someone could help me with some good sources or could answer a few questions.

He was part of D Co 66th AR possibly under 2AD and would have went ashore at Normandy around D+3 according to some sites I found.

My question is everything it listed by battalion such as 3/66 AR with no mention of the companies. I’m trying to figure out what battalion he was apart of and I’m wondering if no battalion had the same company designation in the regiment?

For example 1/66 has A-D Co, 2/66 has E-I Co etc... or did each battalion have the same designations for companies like A Co 1/66 and A Co 2/66?

Also turn out 66th AR was deployed to OEF in Paktika the same time I was which was also pretty cool.

How did you request this?

https://www.archives.gov/veterans/military-service-records

It would appear that your sources are correct, in that the 2 AD did land at Normandy on 9 June.  CGSC has some WWII AARs in their electronic library for the 66th AR and 2nd AD.  My apologies if you've seen these already; if not, here are the links to some reports that you may find interesting:

Operations report for period June 1-30 inclusive (2nd Armored Division)

After action report, 66th Armored Regiment, 2nd Armored Division, Aug 44 thru May 45

G-3 report: 2d Armored Division

Unit Report No. 1, 66th Armored Regiment

Thanks. I haven’t seen those before. That’s exactly what I was looking for tho. Hopefully I can find the rest of the AARs. I read about 30 pages last night and from the sounds of it they were pretty much in the shit from the start.

This is a family photo possibly taken by my grandfather that may be his tank crew. The back states its just before they head to Berlin. Can anyone Identify the type of tank they are in front of?

To the right is a Sherman.  What they're standing in front of looks too wide and low to be a Sherman.  Either an M-26 Pershing or some variety of Tank Destroyer is my guess.

Photo shows them standing in front of a m26 Pershing. Puts the time frame in winter spring 45.

Pershing was my guess based on how low the hull is and the gun port. I read that that Pershing’s were in very limited service towards the end of the war. The bumper number is 36. Would this be third platoon commander take similar to how things are done today?

Knew a fella who went to Europe in Pershings.  They ended up in what is now Czechia, and were tired of C-rats.  So they mounted a M1919 in front of the passenger of a jeep and went deer hunting.

D coy was generally light tanks or in this case, the M-5 Stuarts.

M-26 Pershing.  That may not be their vehicle though.

Agreeing, M26 Pershing on the left and an M4A1 76mm Wet Stowage Sherman on the right.

As late as October 1944 there was a Golf Co\66 Armored Regiment listed as assigned to 2 AD, so up to that point the companies were still using the older A Co through I Co regiment TOE. By the end of 1944 armored regiments adopted the generic A Co through E Co BN TOE. Unless you can locate specific AAR's from earlier in the war, your grandfather's service will likely be linked to specific BN's like 3\66, and not companies themselves.

Coys A-C were M4 Shermans.  Co. D was M-5 Stuarts.

Mind you, there were very many different models of Shermans that a unit could have.  It all depended on what got shot up and what replaced it.