I did this:
Goto, Central Administration >
Operations > Solution Management
Drill into the SLK -> Click Retract
Wait a minute, drill into SLK again, then delete it.
Modify the "AddSolution.bat" file from 1.3 and change the reference to point to your SLK1.4 wsp.
Within Central Administration > Operations >
Solution Management, deploy the solution.
Run the SQL, then upload the .xml in Central Admin.
I probably made everything a lot more complicated than it needed to be, but everything seems to be working so far.