When I installed the headers, I replaced the plugs and there was evidence of oil, but it didn't blow blue smoke like it does now.

I was told the motor was rebuilt to stock specs but the idle seems a bit rough for a stock cam. Another symptom is low vacuum, about 12-13 inhg at idle.

Here are some video links of it idling and a rev that shows some of the blue smoke.

Idle w/carb

Idle w/EFI

Quick Rev