My 427 is actually a '62 406FE NASCAR block bored to 427 with cross-bolt mains (515HP), close ratio toploader and the Jag rear (Ind. with twin coil overs) has 3:31 gears. It works quite well.
My 'bird has its original 390 FE bored 30-over, so its actually a 396. Stock heads and crank. Lots of oiling mods including 0.075" restrictors to the heads to supply the PQ roller rocker set. I have a Lunati Voodoo RV type roller cam, retro-fit roller lifters, two-row roller timing set. I like to roll, lol.
For the intake I have a Edelbrok Victor single plane, and on top of that a FAST EZ EFI 1.0. Exhaust is Sanderson Hot Rod headers, 2.5" dual exhaust with an H pipe, Borla mufflers and Hushpower bullet style muffs mounted as resonators. Yup- four mufflers. It's still loud.
Ignition is an MSD Ready-to-Run with a 6A box.
I also have a March Serpentine belt kit with a 100 amp alternator, Chevy power steering pump and a Sanden style "peanut" AC compressor hidden down low on the passenger side. I routed the AC lines outside of the engine bay to keep it all neat and tidy.
The 100 amp required me to upgrade the electrical system, so I have a power box from a 2005 Focus mounted under the hood to back feed the OE panel, and I use the relays to trigger my high amp accessories. All the electrical is encased in woven nylon sheath like my '12 Chryco Jeep.
MY AC is a Vintage Air Gen IV that uses my OE heat only controls and a microprocessor. It blends AC and heat with servos and the defrost cycle dehumidifies, like a modern car.
I have a Tanks, Inc. in-tank electric fuel pump, steel feed and return lines, Russel braided hose to match the electrical, and black anodized Russel AN fittings. The big fuel filter is hidden in the driver's fender, along with a late model carbon canister that collects the tank vapors.
My last mod was an AOD from an '88 Crown Vic. That has a high horsepower kit and a custom mount to the big block. It retains the locking torque converter and shifts into OD at about 52 mph, unless I'm romping on it. I have the original 3.00-1 rear so at 70mph the engine is loafing along at 1800 RPMs. I use the OE cooling circuit and an auxiliary filter which is the same size/ type as my oil filter.