I would try to get your hands on a leakdown tester (test with your rad cap open) or a radiator pressure tester and check that first if the smoke was white.
------------------------------------------------------------------ 1992 300ZX NA 5 Sp (Dead) 1990 300ZX NA Auto 2+2 (Dead) 1990 300ZX TT 5 Sp (Building) 2004 G35 Sport 6MT (DD)