Help 360 2bbl tuning

Have a stock 360 out of a rv, motor starts right up, idles great, when you give it gas it falls on it's face but give it gas again it'll rev fine. When you drivin down road runs pretty well when your into the gas. I got it warm was able to drive down the road but after 5 mins started missing real bad also, and I didn't change anything.
Plugs are white I know it's lean but I can't get it to riches up! Any help on tuning the holley 2 bbl be great looks like part number is r7871a, newer stickers on the carb that states it's. A reman, the rv only had 50k miles on it also.

Cap looks brand new, new rotor button, plugs look new, wires looks new, my orange box is good, running 10 deg timing at idle

Thanks