Welcome Ken:
Yes it's unfortunate, but until you posted yesterday, there has been no activity in this area regarding the 49th since 2005! A real shame, but who know what else we can find out in the interim, right?
I hope you are able to piece together at least a brief history with the memories and items your mother is willing to supply. Yes, DO get them before it's too late.
Unfortunately you are amongst the thousands of sons and daughters who are desperately trying to find out anything they can about their fathers. But always remember there is a ray of hope; my story is one of those hopeful cases and shows that anything IS possible. 
I am going to try and email a few of the people who posted here and see if I can get in touch with them for you.
Proud Daughter of Walter (Monday) Poniedzialek
540th Engineer Combat Regiment, 2833rd Bn, H&S Co, 4th Platoon
There's "No Bridge Too Far"