That is a really old "tune up kit" from the early>mid 70's.
The timing light does not have an inductive pickup to clamps around the spark plug cable. Instead, those male and female terminals go in series (in line) with the designated spark plug lead for timing purposes. In the case of an IH sv, that would be cylinder #8. That light is a "self-powered" unit and does not require connection to the vehicle battery...as such it has a relatively weak neon bulb and needs to be used in a "dark" environment.
The yellow alligators would clamp to the battery terminal on the starter, and the "s" terminal on the starter solenoid, that light has an integrated "remote starter switch", so you can crank the engine over for setting dwell or finding tdc on the timing grid.
Those kits were typically sold in discount houses and auto parts locations and aren't considered commercial-level tools, though they have become "collectible" over the years and are certainly adequate for a home shop.
As for the dwell meter, the normal hookup for an inductive ignition system would have the black clamp going to a ground point, and the red lead would connect to the ignition coil negative (-) terminal. The control switch on the front of the handle then selects either a "dwell" reading, or a tachometer reading, normally used for setting idle speed since those are a high resolution analog display.
I just picked up a very similar kal-equip tach/dwell meter from the 70's that needs some refurbishing. The instrument you have will display the dwell on your Holley gold box ignition system in exactly the same manner as regards a breaker point system. The dwell on a gold box units is adjusted by setting the reluctor air gap which is adjustable, but you should not deviate from the specification given for the reluctor air gap which is 0.008". That instrument will display a dwell reading of a nominal 30* with the engine running at idle with a gold box system.
I'll move this thread to a more appropriate sub-forum!
her's pic's
