I had to replace the headliner, alternator, battery, and some other things. I put all new Monroe airs-shocks on all four corners, with airshocks in back. Last March I had a Flow-master put on it, but it wasn't that loud. Around last winter I almost burnt the motor up (damn, idiot lights) which led to the motor getting a mild knock in it. I drove it like that for about a year until the motor finally bit the dust. It was getting too much crankcase blow-by spitting oil up through the carburetor. In my opinion the 305's were the poorest engines ever built.
It was a fun car to drive. When ever the pavement was wet you could be driving at 25 mph and punch it, and you spin the tires for at least a block until the car finally picked up traction.
These cars make perfect super-cars, the only thing is that if you make it a hotrod then you need to add some weight to the rear-end or you won't get any traction. The after-market parts for these cars are pretty plentiful.
These cars are pretty tough too. I have hit so many things that it still managed to stay running. The interior is pretty plain and convenient. All the controls are within an arms reach. The 40/60 bench seats were pretty comfy. Back behind the seats you had plenty of space to put a killer system. The flaw that the interior lacked was a full set of gauges. Instead, it had idiot lights, you can ruin a motor by the lights not coming on, and if they do come on then that is when you need to stop.
Yes they did have full set of gauges in a 1982 elcamino mine has all of themand is stck with a tach temp speed oil pressure and volts.
The 305 is well put together if you drove it for a year with a rod knock!!