Which components to replace, which to reuse?

I have 93 with factory air that no longer works. The system had been converted with a cheap kit by a previous owner. I attempted a recharge and the system will take nothing, I think it is pretty full with oil. I would like to do all the work other than charging to get it up and going again and dont want to buy any special tools if possible. My question is what components need to be replaced and what can be easily cleaned and reused, by easily I mean with common household tools, etc. Thanks.

Having just converted mine, here's my take:
Assuming everything works
Replace accumulator
Remove and replace orifice. If covered in black gunk, replace compressor and condensor.
If orifice is fine, remove and flush condensor; remove and drain compressor. Flush evaporator in system or removed. Flush hoses. Replace all o-rings.
Put 2 oz PAG100 oil in condensor, 2oz in compressor and 3 oz in accumulator.
Evacuate system
Add 20-24 oz R134a refrigerant

Minimum set of components to replace - accumulator and orifice.
Minimum set of tools - A/C manifold gauges ($49) vacuum pump ($100) and A/C fitting tool ($6)

Tonoight's reading assignment - A/C stickies in A/C and Heating subforum:
http://www.explorerforum.com/forums/forumdisplay.php?s=&daysprune=-1&f=123

Ask questions. What does it mean that the system will accept nothing? The compressor does not come on?

I can hear the compressor come on, but when attempting to service the system the guage reads 0 psi and nothing will flow into the system.

The compressor only comes on momentarily so there is little or no freon in the system.

As I said I'm not trying to spend much on tools, would these be adequate?
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92649
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92475

If not, I assume I could do the work myself and have them pull a vacum before they charge it.

Yes, the tools are adequate. They are used often here. Be aware that the vacuum pump requires a source of compressed air at 4.2 cfm

The power has been off here for six hours because the transformer blew; So I must be a little dense. When you say:
"I can hear the compressor come on, but when attempting to service the system the guage reads 0 psi and nothing will flow into the system."

Does this mean you are attempting to charge the system with refrigerant, perhaps a cheapie kit from Autozone? There hasn't been too much success with them, although they seem straightforward and should work. The gauges are notoriously inaccurate.

Your assessment that the cycling of the compressor on and off indicates a low charge is reasonable, but also means there is something in the system to get the pressure up high enough to cycle on the switch;so you do not appear to have a large leak.

Before opening the system, read the stickies, ask questions if you are unsure of anything, and connect the gauges. Let us know pressures and ambient temperature.

I bought the Haynes Heating and A/C manual today so I have a pretty good understanding off the A/C system. However the book is not vehicle specific and it refers me to the vehicle specific Haynes for removing A/C components, mine has nothing about that in it. So my two further questions are how to remove the accumulator and how to remove/or drain and fill the compressor with oil.

The 91-94 Haynes Explorer book contains cooling system component removal instructions.
Instructions assume system is empty of refrigerant, wear goggles when opening.
1. Remove bolt holding refrigerant lines onto rear of compressor.
2. Remove connector and bolts holding compressor to bracket
3. Compressor should be free
4. Suspend compressor over measuring cup and drain oil. Turn compressor using 10 mm wrench. Oil will shoot out discharge port, be careful. It is not recommended to flush compressor.
5. Fill with PAG100 oil the same amount of removed oil or 3oz, whichever's greater. Pour in suction port, very little will go in discharge port. Avoid temptation to quickly turn compressor.
6. Replace o'rings and attach lines. Torque bolt to 15 ft/lb +/- 2
7. Bolt to bracket.
8. Turn compressor several times to distribute oil.

Accumulator removal and replacement is straight forward. 1. Loosen the nut holding the evaporator line and connector to pressure switch
2. Remove the compressor line with special A/C connection tool
3. Loosen screw holding bracket.
4. Remove accumulator, pulling straight up.
5. Transfer switch.
6. Pour 2 oz of PAG 100 oil into accumulator
7. Installation is reverse of removal, use new oil rings

Some advice:
Keep caps on replacement accumulator until necessary to remove for installation. Change the orifice.

Make sure when you replace O rings that you use the GREEN ones. I also recommend going to an AC supply house and getting the NyLog lube/sealant made for 134a. Shamaal is, as always it seems, right on with his AC advice!

Yeah, thanks guys. My A/C is up and running after repalcing the accumulator and orifice tube. Cost me about $150, took it to a Militar Auto Skills Center, did the work my myself then one of the supervisors there hooked it up to the A/C machine to confirm no leaks added some oil and charged it right up. For whatever reason my Haynes doesnt cover removing those components it says something like the A/C is a complex system and service and repairs should be left to a professional.

I'm using a Haynes Manual titled ForD Explorer 1991 thru 1999, published in 1999. Section 3-15 addresses the A/C.