If you are changing the compressor yourself, you are surely skilled enough and have adequate tools to flush the system yourself. Additionally contact your local auto a/c shop and check into a suction side filter. Since you lost the compressor, this will help catch the junk in the system before it reaches your new compressor.
Simply remove the compressor and start removing all your hoses. Get a flush gun that you can pour in the flushing agent, then pressurize. Use this to flush all the hoses, the evaporator, condensor and the expansion valve. Put it back together with new o-rings and nylog. You can get a kit of o-rings and the nylog o-ring lube from acsource.com for about $25.
Blow out all the flushing agent thoroughly, put in the correct amount of oil (you can find this spec at aircondition.com, D's Technical Pages) Put in the new filter drier and then take it to the a/c shop for evacuation and charging. Stay with R12, it is down to about $29 per can and is the cheapest component of your a/c system. These cars dp not convert to an alternate refrigerant well.