Is it 2-wheel or 4-wheel drive?
What trans does it have?
I bought two 1977 full size trucks in 77 - a 1-ton (utility spec HD 3/4 ton sold to gas/electric companies and also the MIL-Spec 'COPO' unit ...
yup - GM had a COPO code for this option ...) pickup and a 3/4-ton HD Suburban - both were 4-wheel drive.
The Suburban had a 454/TH400/Auto-4-wheel drive driveline.
The Pickup has (still own it) a 350/SM465 (4speed w/granny)/Manual 4-wheel drive driveline.
The 454 AC mounts and other accessory drives will NOT work/bolt to a Big Block
The Axial design AC unit is on the left (drivers) side and the Alternator is on the right (pass) side on both, but there are some minor differences in location and belt routing that precludes interchange.
They changed these location on later models when they changed to the Rotary design AC compressors.
The transmission mount patterns are the same, but the torque output of the 454 is way above the TH350 rating, so it wouldn't be reliable for long ...
The BBC and HD 4X4 units also had an added support brace that ran from the bellhousing to the transfer case to help support the added weight and power.
The engine mounts are the functionally the same and will bolt up. But ... you may effect location of some support systems if you do not grab these from a donor vehicle with a 454 for the swap.
Best option - IJMHO's - would be to locate a 'donor' 1977 (or compatible year model) and use all the mounts, supports and electric wiring from it as required.
You can find these for pretty reasonable prices in most areas. This would give you all the parts needed and maybe a rebuildable core(s) for your Camaro in the future.
I've parted out a couple of these years and the left over parts are easy to sell to recoup some of your investment.
I still have a couple rear quarters and a 14-bolt rear axle in the shop from the last one ...
BTW - here is a late 70's BBC full size pickup engine bay for reference -