The 208 vs 241 bolt patterns and spline engagement are EXACTLY the same. I've replaced 208s with 241s and vice verse. The shifters are different. The slot for the shifter is 90* off between the 208 and 241. Simply cut the shifter end off, turn it 90* and weld it back to the shifter and you will be good to go. Someone should be able to get a picture of a modded one.
The 700R4 and TH350 have different output shaft lengths. A TH350 adapter is longer to deal with this, if you were to use a 700R4 adapter it would work but you would need a spacer. Adapters for a 700R4 will bolt to a TH350 and vice versa.
The amount of shaft that engages into the 208 is the same as the 241, no difference.