Old Car Squeaks, Rattles and Groans

The dash has a channel along the bottom that a bolt or screw can lay in. The flasher that should be in a clip on ashtray hanger might be laying in this channel too. The rubber bumpers at glove box door and ashtray door are a must.
Now the doors... The window regulaters get loose motion in the bearings behind the winder handle. I use bearing assemblies from rear doors of 4 door cars to restore those. If you have to push the button on the outer door handle a long way before the latch pops that is adjustable through a hole drilled in the door edge with a long allen wrench (1/8" I think). That adjustment will cure a rattle too. Loosen the screw and allow the springs to move the parts then retighten and done. The 67 model has a long phillips head screw through the painted portion of the inner door where the 68 model has a small plastic plug in that hole. The screw is stll there, just redesigned and I was told once that a rattle came from those by a guy that worked for a Chrysler dealer in Ohio. He taught me soooo much about my car.
I have to add that hotrod stuff like a cam will shake a car apart just like a Harley motor cycle. Owners of those know why it came with a small tool kit.
Same reason those old Jeep CJs had very little interior or door parts to shake apart.
My 67 notchback (here I go bragging) has one noise. The passengers seatbelt buckle will tap against the side of the console when wife leaves it there. I brush it to the center of the seat to cure. Guess I should add you'll hardly hear or tell the 273 is running and it might spin a tire if you kick it around a corner. Hope some of this helps.