Hi Paul,
Without some surgery you're not really able to inspect anything on the vertical stabilizer, I have not heard or know of any issues there.
You will want to inspect the longerons in the fuselage where the horizontal stabilizer attaches. These longerons can have broken glue joints from handling or even be broken from over-torquing of the horizontal stabilizer attachment points. Reference Service Memo #12 found here:
http://www.culvercadet.com/servicememos/servicememo12.pdfWhile the stabilizer is off the airplane you'll want to inspect/feel the 1/16" plywood bond to the ribs with gentle squeezes and light taps with your knuckles. Also rotating/shaking the horizontal stabilizer around while off the airplane listening for loose glue rattling around inside there. If you hear rattling, hopefully it is just the drips of glue that have broken loose from the sides of the ribs. On my airplane I removed the lower plywood skin to inspect and found loose drips of dried glue and two ribs that had broken glue joints to the plywood.
Easily repaired but the process is a little time consuming with cleaning, replacing all the loose gussets and everything. Do it right, when it goes back together it needs to be good for another 80 years!
I hope that helps answer your question!
Joe