chrisremo - you can get most of the way with just the clue numbers. For instance (SH)^Y is the 20th down clue. It’s value cannot be less than 20. There are 47 clues in total and six after that on the down list so it’s maximum possible value is 41 (probably less).
There are a limited number of values for SH and Y.
Every number between 1 and a maximum of less than 47 need to be represented so if two consecutive down clues miss a number or numbers (say 23 followed by 25) then the missing number(s) (24) must be in the across clues.
Hope that gets you started.