Duster running rich

Engine is 340 30 over. Zero decked. Kb pistons. 1.6 Harlan sharp rockers. Cam 292/508. No idea on install and timing as it was built 15 years ago by my uncle who is now deceased. Head have 202 160 valves. Holley electric fuel pump. Engine tuning is not my thing as I'm a body and paint guy. The information I'm giving is the from the stack of invoices he left in a folder. I really do appreciate the help. Thank you all

292/508 Have a grand time with that one getting a clean idle.

You have to know timing to get it set up. Setting it by the "book" will be an absolute disaster!