Identifing a 60 model

[cheby267]

I'm working on 60 model Chevy swb stepside , it's been a long term project . Drivetrain is done with an updated FI350/700r combo , vintage air , dash and gauges , tilt and p/s . Now it's time for the suspension / brakes , which will be a disc/drum update with power, new bushings and joints and a front swaybar . One thing has me scratching my head , it has front coil springs …….. is this correct , could you get coils in 60 ? If not and the frame has been swapped out or something , how do I identify what model it actually is ?