Pull the spark plugs and read their condition. They should be light tan in color, not black and wet with oil. The gaps should be in spec. If any are wide, replace the set. If any seem wet with fuel, those are likely not firing. Check the plug wires and distributor cap and rotor for burns and corrosion. If they are all a bit sooty, the carburetor may be too rich and need rebuilding. Same with very light tan (a lean condition) with some blistering or burned electrodes on all plugs.
Consider that 1976 was in the peak years for complicated, poorly executed emission controls and likely would surge when brand NEW! Considering all the vacuum lines and vacuum operated accessories and emission controls, if you haven’t replaced EVERY vacuum line with brand new, do so right now before even starting anything else!
I assumed you’d be working on this yourself since finding a mechanic who’d even touch it would be almost impossible.