I have had my 67 Firebird 400 4 speed for over 20 years. I ran in the 180-190 range, until I took of the after market flex fan and installed the original fan (I like everything original). Now it's running 190-230 and sometimes 240. I installed the original 1 1/2 then the 2/12 spacer, but its not helping. What is the original spacer length and what suggestions do you have? Right now, I have the 2 1/2 spacer and it sits about 3 inches from the radiator. Thanks in advance for your feedback...