You don’t need to do ANYTHING if you are running current AmiQuote version 3.22 as it already has all correct format files in place.
You should really read the Knowledge Base
This explains precisely what to do if you want to have data adjusted for splits AND dividends.
Current (as of July 24) format for data adjusted for SPLITS only is:
# default in AmiQuote 3.22
Format for data adjusted for splits and dividends
Everybody please read the FAQ and Knowledge Base.