Pretty sure vent from pump to tank was for AC cars. Mine has it
X2 on venting through the cap on 67s Do a search on this site, there are some threads with part numbers. The repos with 'ears' do not fit correctly and are wrong for 67. I have a pic somewhere of the correct cap, let me know if you'd like me to post it.
1967 Firebird Convertible 1980 Firebird Formula Turbo