[12secondnova]

The stock accessories will work. Even the stock fan fits in the factory shroud.

And you will need to change the oil pan, the stock one hangs down an inch below the frame so with your lower kit you will probably want to change it. I bought the cheap 'gm muscle car swap pan' from gm for about $150. The dimensions say its an inch shallower than the stock truck pan but I haven't installed my engine yet so I can't speak to whether it fully tucks above the frame.

The 4l80 will need the output shaft and the tailshaft changed.

Driveshaft will need to be shortened.

Not sure about the A/C never installed it but vintage seems to be the choice of alot of people.