headlights/taillights - check fuses (headlamps are probably circuit breaker protected) or headlamp switch.

Reverse lights - controlled from transmission selector, I think. By that I mean - put tranny in reverse, and one of the pins on the transmission harness goes "hot" to turn on the reverse lights.

Would have been nice if you knew whether this worked before the engine swap, although the diagnostic methods are probably the same regardless.