It came with one catalytic converter
Yes, if it came from the factory with a converter.
All El Camino's with catalytic convertors were "unleaded" fuel only cars; 1975-1987.
... what about them..?
No, they're 2 totally different bodystyles
Yes
.35.
The back glass from any 1978 or newer El Camino or Caballero will work.
Chevy Malibu. Mostly.
Go to manheimgold.com and look it up.
my 79 Caballero is 3372 lbs. has a 350 motor.
1,8,4,3,6,5,7,2 with numbers 1,3,5,7 being on the drivers side.
A '79 datsun pick up would have came with a 2.0L L20B engine.