The Registrar for the Mk I S Minis of the Mini Cooper Register has been collecting FE numbers for a long time and may be able to help you even if you are not a member. Contact Simon at mk1Sregistrar (at) minicooper (dot) org  

Thanks guys for the input

Am I correct that the VIN tag is not present on the fan shroud?  

Check the dot code on the glass against Parnell's book.  On the slam panel look for the body tag.  The folks at Heritage may be able to work with that number.  If the boot lid is also present with those doors, look for a date stamp on the lock.  If the high/low beam dip switch is on the floor, look for a date code on it.  If the wiper motor is on the car look for a date code stamped on its aluminum cover.

Body and doors and no numbers will be hard to verify as ever a Cooper S.  As RH tank and (on block) oil cooler were optional before 1966 so having the tank is no verification to an S.  An S would need to have the appropriate holes on the RH inner fender for the brake booster brackets and the relocated regulator and fuse box.

September 64 was major change to the mini sedan, major being hydrolastic.  Brackets for hydro pipes and rear bump stop reinforcements fazed in with last of dry cars.  Sun visors (as previously mentioned) changed from center chrome hinge to pivoting end mount, Hole in front of door frame for switch for interior lamp added.  Sounds like you have post Sept 64 shell (more changes for Jan 66).

Can you tell an Oct - Dec. 64 shell from a 1965?  Without VIN or body numbers to reference it is not likely.  The FE number by the rad on the LH inner fender, if present, could be compared with other cars of known vintage to narrow down production time.

Body and doors only. I know it is either 64/65 from the sun visors.

Start with a heritage certificate, then see how much of the car agrees with that, and there are many parts date coded on the car as well, Parnell guide to coopers is a great resource. 

Anyway to determine if the Cooper s body is a 64 v 65?