i washed the engine off in my 68 small block ss/rs,but i gave it 7 hours of drying out time,it is getting plenty of fuel,stays running at 1200 rpm + but when it goes in reverse or any gear it dies..i think it might be points or a loose wire....any help?

Probaly still wet in cap. Remove cap and spray some WD-40 in it. also on plug wires at plug.