This is one of my old rides.. wish I still had it...
1965 Mustang GT, 289 4bl factory.
Everything was original or NOS except the engine.
It looked stock, but that's the way I went with it, engine wise.
The block heads tranny etc, all matched the body, but unless you took off the factory air filter, you never saw the Holly or realized that the intake was aluminum painted to match the factory item.
About the only thing that didn't match by the year were the rims, '66 in the front and '67 styled steel wheels in the rear. I went with them due to the '65 ssw did not have buety rings and the '67 was a tad wider to allow a hair more rubber yet retain the 'stock' look.
Unfortunately, the car met it's demise when i got stupid and sold it.. Got a call a few weeks later that they cracked the block....