A little on Clemens.
https://www.newspapers.com/clip/3155...tar_and_times/
https://www.newspapers.com/clip/3155..._postdispatch/
Another article mentions his body being returned to the US in 1948.
Just to confuse things a little more:
On fold3 his headstone request says he was in the 401st BS, 91st BG.
https://www.fold3.com/image/317820724
His grave shows also the 401st BS:
https://www.findagrave.com/memorial/...fred-j-clemens
On this link (search for Clemens) it says that on April 26, 1943 T/Sgt Clemens (him?) was included with some others attached to the 91st BG from the 94th BG.
http://www.91stbombgroup.com/Dailies/401st1943.html