Depressing Dyno results. Need advise

Yes, new valve springs for sure. If those are from a 77 they are old and tired, I would do that first.

You need to know where the timing is not just where it ran good, buy a timing light and and a damper tape so you know for sure. I would have already done the 3/8 fuel line and electric pump but I don't think that is your major problem assuming the pump is in good working order.

I have found most off the shelf carbs are too lean for a Mopar, they set those things up for Chevy so get yourself a jet assortment kit for your next dyno visit, richen up the carb jets 2 numbers at a time until the power drops off and then go back one number at a time until you get the peak power point.

Spark plug heat range is also another factor to examine as is the stock ignition, but since your set up is very mild the stock box may be OK, I would probably go with an orange box or an MSD 6al though and an MSD coil.

You should try some spark plugs are few heat ranges colder and hotter, examine them carefully after a dyno pull to check for signs of detonation, overheating and air/fuel ratio. Do some interweb searching on this and you'll find some picture examples to go by.