Spudz

The other two options are using the 84' Maxima
rear bracket with the 280 rear calipers , or a
custom rear bracket with Wilwood or Outlaw
rear calipers and no parking brake. I do know
some guys who went this way and use a line
lock as their parking brake.

Bleach

No, you can't just swap the rear calipers from a 79. The 280zx rear brake calipers attach to a mount that is one solid part of the axel. The 84 Maxima has the same rear disc design as the 1981-83 280zx, but with one difference. It has a removable caliper mount. This makes it very easy to remove your rear drum and shoes, then bolt on the Maxima mount to the mounting bolts of the dust plate (after you have removed the dust plate) and then just use some ZX calipers. I prefer the later 280zx designed calipers, or basically use the 84 Maxima calipers with the caliper mounts. They have very low clearance on the outside, so you don't have to worry so much about what wheels you use. They run fine with even 14 inch rims.

I have a 1984 Maxima! ...but its my wife's car, so you can't buy the brakes off of it. hehe...

As far as putting big brakes on a 1980 280zx, you'll have to go aftermarket I think. There is a swap using 1984-85 300ZX brakes, but I think its mainly a vented rotor, not much else is an improvement. The first year or so of the 300ZX still has a 4-lug pattern, that's why later years dont' work with their 5-lug pattern.

Bleach

If you successfully swap in rear calipers from a 280zx or Maxima, then the caliper itself is already set up for a brake cable attachment. So yes, you will have a parking brake.

It is the aftermarket calipers that don't have a parking brake attachment. (or if you use "front" calipers from another car on the rear of your Z) Those aftermarket swaps are much more expensive too. For a 240Z, do the 4-piston Toyota 4x4 calipers in front and a single piston ZX caliper in the back. That should give you plenty of stopping power even for racing.... but of course, you and ALWAYS go bigger.. but I don't think its nessisary.