my 1982 c10 truck failed my smog test?

Yes Hello I have 1982 c0 truck. I bought it with paperwork from a smog saying it failed the evap test only. I fixed the crack in the fuel line and then put in new plugs, wires, and a pcv valve. This new shop tested it and said its a gross polluter only 6 months after a passing test. on the hc it went from 47 to 378 the co went from 0.18 to 2.9 and they said the evap test failed again too. also the visual. this truck has been fiddled with yes like they put in an electric tranny and plugged off the vac lines. I mean it does run a little rough but how in 6 months can the number go from 47 to 378. The shop wanted me to do a pretest and when I said no he went to the technician and had a talk with him. I also saw the technician use a drill and put a hole in something under my truck. why would they drill a hole and what would that even do? ty ahead of time for your answers