I think the coil wires are swapped at the coil terminals. Also the tach goes on the -. The colors suggest it is wrong. Since your system is not CDI, most comments, posted are not correct..
I cannot tell HOW the coil is wired. Orange seems to be correctly hooked to coil NEG, but where is the red? Coil wires in the photo suggest that the original coil + wire is hooked up, which should be fine.
Your mechanic PROBABLY hooked the tach up to the tach output wire. This wire, in fact, may NOT be where you want to hook that tach. You in fact may want to hook the tach to the coil NEG terminal as original
The destructions show distributor wiring should be
orange--to coil neg
red--to coil + and to switched "ignition run" voltage
