Need a one inch longer BBC Z-bar for clutch, and I was under the impression all the BBC's in a Nova were the solid lifter 375 horse 396 version; which means no A/C since GM never shipped A/C with a solid lifter car (except a few limited edition Corvettes).
Actually you will need to swap the P/S pump as well as the brackets as the BBC has the return hose (low pressure) in a different location to clear the heads.
If you have A/C currently you have the BBC radiator core support as it has a larger opening for the required four core Harrison radiator already. I have all the brackets you need to install an A/C with a BBC if you desire to do so as I got an extra set off of a '70 Chevelle (long water pump).
Your existing alternator bolts up from the small block but will not have enough umpph to keep the battery charged if you start your motor a lot because a BBC uses a high torque starter motor (has 5/8" longer armature winding than the SBC starter so the power lug is spaced out that much further forward of the solenoid with a brass piece making the connection) with the mounting bolts diagonally attached instead of across from each other so that it will not bolt up with the smaller diameter SBC flywheel (fewer number of teeth on starter ring).
The pedestal frame mounts raise and shift the crank center-line to the passenger side by one inch to clear the steering box. Because of this the holes in the BBC transmission cross member are shifted to the passenger side one inch also. There isn't a full set of cast iron exhaust manifolds around at a reasonable price, so I would only consider tube style headers for your exhaust unless you want the numbers matching thing. Distributor for a BBC has a different part number because of the different ignition curve but your SBC one can be modified with weights and springs to work.
BBC were only available in an SS car which means you need to have all of the SS equipment installed as well (multileaf rear springs, HD shock, 12 bolt rear end, HD battery, HD alternator, gauge package (installed in optional console), 15x7 inch Rally style wheels, disc brakes, F70-15 Polyglass Goodyear Raised White Letter tires, and SS trim package. This is of course unless you ordered it as a COPO plain wrapper car which shipped any way you wanted; he he! :thumbsup:
I will see if I can work up a list of all of the parts needed as this is a frequently asked question.
Big Dave