Daisy Red ryder

My nephew has given me his Red Ryder to fix.He cocked it and put the lever back to normal and nothing happened.The lever now just hangs doing nothing.I’ve tried to remove the trigger group but part of the frame is rivetted.How can I remove the trigger assembly?

Any help or info on finding a diagram would be appreciated!

Also I was sad to find,as I removed the wooden fore end,a little sticker with “Made in China” on it.

Bob