Hi. I am at the reunion and found out that this hotel has a very strong wireless connection so I am writing on Day 1 of my vacation. Anyway...
Please look at the history page on the main site. I have all the emblems from each unit, the 36th, 39th and 540th. The 36th and the 540th both use the seahorse emblem and they were both in North Africa, Sicily, Italy, France, Ardennes/Alsace and Germany. From what you are describing I would have to say that he was with the 36th.
http://www.6thcorpscombatengineers.com/history.htm
I happen to be at their reunion in Lebanon, PA this weekend. Wow, what a coincidence. I will show them your post tomorrow morning. They have a complete roster of all the men who served with them.
I will check in tomorrow and let you know.
Proud Daughter of Walter (Monday) Poniedzialek
540th Engineer Combat Regiment, 2833rd Bn, H&S Co, 4th Platoon
There's "No Bridge Too Far"