What would it look like to wire the 74LS1581 as a 1 of 4 data selector?

 

Welcome to the forums.

Please don't hijack threads - always start your own.

Some confusion here - are you sure about that device number? Do you know about 'LS139's?

 

I guess you are referring to the 74158 quad 2-to-1 MUX.

Think about it. If its function is to select one out of a pair, and you have four items (2 pairs), how about selecting one item out of each pair, and doing that again for the resulting pair.

As usual, you must post a bit of work before receiving any help in this forum.