New car, new problems; 76 Duster 318

Sorry if I repeat what has been said. Check the choke and float level. It may be not opening causing the plugs to foul ut. Same with the float level. It may be too high and dripping fuel down the intake when it's not needed. Dash lights/Gauges. Fuse first. If it's good, the pins may be broken on the back of the dash cluster, or as simple as the harness not plugged in. Same with the speedo. It might not be plugged completely into the housing, or the clip at the cluster is broke. I recently replaced my headlight switch and speedo cable, and got the parts from Rockauto for under $40.00 shipped to my door. You may be able to purchase locally for the same price or cheaper, and many auto stores offer a Military discount.
Good luck!