How To Clean Metal Tapered Candle Mold

[mtnb]

I haven't made candles in years. Yesterday I found my metal mold that makes 6 tapered candles. It's been in storage for a very long time and is a bit greasy and has these dust bunnies and dirt down in the tapered part. What is the best way to clean them? I googled but all suggestions for cleaning were for votive type candles where you can get a rag into them to wipe out. That's obviously not possible with these. One link said never to use soap and water but to use alcohol. I guess I could pour some alcohol into them and swish it around and hope that will get all the residue? How would you suggest I clean them?