Variable Ranking after models have been generated

I have a reasonably large dataset with the following characteristics:
20,000 signal events
80,000 background events
400 potential variables

I am using various TMVA classifiers to help me first pick the 10 or 20 most important variables from the 400 variables. After a few failed attempts, I was able to book enough classifiers for my analysis and run it through the TMVAfactory set up.

I have the weight files from all the classifiers but the variable ranking report printed on ROOT console has been lost. Is there a way I can generate the Variable Ranking from these weight files alone?