I am trying to create raw transactions according to the excellent answer of runeks here: How to redeem a basic Tx?
But there he starts with a private key in hex format
18E14A7B6A307F426A94F8114701E7C8E774E7F9A47E2C2035DB29A206321725
and I have one in base58 given by bitcoin-cli dumpprivkey:
bitcoin-cli dumpprivkey 154G5oUywHU3pESNy4oBBpkmAGqRZiYxBk
KzRVLwCuCi2tH2PpSNZnwUqPwg6gaqXAM2LWobUurzAsNdC5JesE
How do I get it in hex in the right format?