Fuel starved?

I checked the tank and it's clean. I checked the coils and they look good as well. Pictures below. I installed the gas line which is
Fuel injection hose. Then I tried starting her up. It backfired like a gunshot before it started and idled perfectly. However the oil light stayed in. The oil level is correct and I changed the oil a few weeks ago. WTF? Oil pump?

Maybe you are over thinking this check the light is operating corectly and the pressure switch is also good. It is unlikely the pump is the problem.

As for the coils the usually fail before the cracks appear or at least stop working well
Use a Digital Multi Meter and check the primary and secondary coils for continuity and the secondary for connection to ground which is the steel core.

Have just recently had the issue of the oil pressure light not going off when bike is run up, resolved by checking that I had a 12 volt supply to the switch which I had so replaced pressure switch problem resolved.

Never used a Multi-meter but I'm off to scout one out. I Googled how to test the Coils so I'll doit and report back.
BTW, my oil light has gone out now when I start her up...don't know why it stayed on before but I'm a happy boy now.

The pressure switches can get quite a bit of crud in them and be sticky. Might pay to remove it and use some carb and throttle body cleaner to wash it out.

If your coils are still the original ones fitted to your bike I would replace them anyway. They’re over 30 years old so they are going to be a bit suspect.

These any good?