... what about them..?
They were optional
nope
No, they're 2 totally different bodystyles
Yes
You will need to be more specific. What exactly is wrong? Are they power windows?
All El Camino's with catalytic convertors were "unleaded" fuel only cars; 1975-1987.
The back glass from any 1978 or newer El Camino or Caballero will work.
.35.
Chevy Malibu. Mostly.
It came with one catalytic converter
my 79 Caballero is 3372 lbs. has a 350 motor.
Go to manheimgold.com and look it up.