Things you will need:
1 PS only belt (I got a DAYCO P4K 0853 from MX5 parts UK)
Degass the AC in a shop before you begin
Sockets 8 10 12 14 mm and various small extensions, and a philips head screw driver.
Time it will take to take it out and put every thing back in aprox 3 hrs

Begin by removing the radiator, its very simple undo the top and bottom radiator hose and detach both fans. Unbolt the radiator from the car and lift it out of the way.
You will now have access to remove the condensor that kinda restricts air flow to your radiator. From memory you will need either a 10 or a 12mm socket and a philips head screw driver to remove the pipes leading to this condensor. One of the pipes leads to the AC compressor and the other leads to a bottle near the firewall. Remove them both to get them out of the way. NB pease be carefull if you would like to re install your AC because the pipes are thin aluminum and easily bent.

There is a wire that connects the car to the AC remove it.

To gain access to the AC pump remove the air filter box 3 bolts 12mm and 10 mm.
Basically there are 4 x 12 mm bolts that hold the AC pump to the car's engin. You will need to remove all of them they are not seized on but they are difficult to get off due to the tight space you may want to use some extensions etc.
In this pic you can see the socket is on one of the 12 mm bolts right next to the radiator hose going into the engin. (I opted to remove the radiator hose so I could swing the socket you have removed rad anyway so no coolant loss either way)

I cant show a photo of the other three bolts they are out of sight so to gain a better understanding in this pic you can see the AC compressor and the four bolts sticking out of it those are the 12mm bolts.

Once the four bolts the the AC compressor have been removed it will fall on to the plastic engin under tray. Its difficult to remove from the top of the car because the sway bar is in the way, rather than removing the sway bar you can crawl under the car and undo the little hatch that gives you access to the bottom radiator hose (8mm socket). From there it conviently falls right out of the car

AC is now removed, so its time to put the smaller PS only belt back onto the car.
Losen the two 14 mm bolts the black arrows are on.
The begin the unscrew the 12 mm bolt the red arrow is on. This will give you enough slack to put on the smaller PS only belt.
Begin to tighten the red arrow and when the belt is firmly in place tighten the two 14mm bolts.

When finished without the AC should look like this.

Im going to weigh everything up and record the total weight lost soon.