Bob , the bottom piece is usually referred to as a serpentine valve spring compressor.
It works similar to the perfect handle type that uses a chain and hook.
The hook goes in the engine cylinder or head bolt hole , and the other end gets slid into the slot on the tool.
Somewhere on here Papaw has a photo of his perfect handle one.
I have one that is longer and slimmer than yours.
I think they were for tractors in the 20's , but not sure.