how much trouble to put ac back on?

reassemble everything and install a new dryer and orifice tube. vacuum system and then pressure up with freon if it holds vacuum. You can get a vacuum that works with your air compressor for about 20. and a set of gauges for about 75. from harbor freight. theres a video on youtube that explains everything and how to charge it by a canadian guy thats very good. I did mine last year and had 0 previous experience.