Each save game is a directory of JSON files with .es3 extensions.
You can use the CLI tool "jq" to reformat the files to be easier to read.
The game can read pretty-printed JSON files just fine.

Save files live in C:\Users\<your name>\AppData\LocalLow\Whalenought\Mechajammer\.
The first two saves are "AutoSave" and "QuickSave", the rest are Save1, Save2, ...
To edit your stats, look at Party1.es3.

Things like PainThresh are your stats, 1 is a 1d6 dice.
Things like OneHandedEdge are you skills, 1 is 1 pip, 6 is 1 dice.
If you set all stats to 6 and all skills to 36, they will not all appear on the character sheet, but they are still there.
Things like Max Life Points may also not update properly until you get into combat.
"StudiesChips" and "VirtuesChips" are ways to raise skills/stats in-game, but this is very slow.

You can give yourself inventory items by editing the "Equipped" list.
This is a list of 42 integers. This represents up to 14 items.
Each item has 3 integers: ID, HP, and count.
These are "excellent" tier items: