Huh? Fastbacks came out in late August 1964.

You're confusing it with the GT. That came out in April 1965. Many a fastback rolled down the road before that.

There's no such thing as a "hi-po" block, the 289 High Performance engine used the same block casting as the lowly 289 2V.

Now, if you're wondering if the car is a legit GT, OK. Simple. Is the instrument panel out? Show us a picture of the dash opening. How about the floor under the rear seat? Show us that.

If someone has the Mustang numbers book handy, we should be able to figure your VIN down to build date.

 

I know I have a true 65 GT fastback and know what to look for thats not my question. I'm trying to figure out if 65 GT Fastback could have been Guardsman Blue because mine appears to be that color originally but paint code 'F' shows Arcadian Blue in 65. Also is it possible for April 64 289 block to be in my 65 GT from the factory?

 

I don't think the paint under your carpets and such will be sharp enough to discern between the hues of a color. Sure you can tell it is A blue or A green, as in my case, THE green under my carpets looks like it could any of three colors and looks least like what it actually is. :shrug:
Has it been re-colored or color is just gone? A good place i found to uncover the real color was inside the trunk drain channel, it is too narrow to get a power sander in there so it was likely not prepped as well. Where panels come together, especially over any sealer, wont hold the overcoat as well and you can excavate a bit and might find a more true original color representation.

 

As 22GT notes

You're confusing it with the GT. That came out in April 1965.

You then ask...

Also is it possible for April 64 289 block to be in my 65 GT from the factory?

The answer would be yes, if the engine sat for a year or so before installation. Ask yourself if that seems reasonable...

 

Sorry if first message is confusing but I have a Guardsman Blue 65 GT fastback. I would like it if someone that knows about first year GT Mustangs could respond as I'm more interested in the color question, could an April 65 GT fastback be Guardsman Blue, and if so whats the color code?

My motor question was a long shot as I have heard and read lots of interesting stories about crazy things Ford did in the first year GT's grabbing whatever was available at the time if short on the right parts.

 

I don't see where Guardsman Blue was a 65' color for mustangs. 64 1/2 yes, 66' yes too, but not 65'. Source; Motorbooks Workshop Restoration Guide.

 

You could order your Mustang with any color Ford offered on any other car. If Guardsman Blue was not an "official" Mustang color but was offered on the T'bird you could special order it on a Mustang.

Most Mustangs that still have their original engine find that the engine parts (block, heads, manifolds, etc) were cast in the mold maybe 30 days before the car's assembly date and the engine was assembled only a few days to a week before the car's assembly. It is extremely unlikely that someone "found" a 289 that had been "lost" in the warehouse for a year.

 

You could order your Mustang with any color Ford offered on any other car. If Guardsman Blue was not an "official" Mustang color but was offered on the T'bird you could special order it on a Mustang.

I think this answered the color question.

That is not an original engine block in your Mustang. The original would have a casting of C5AE-6015-E.

Seems this answers the engine question (as far as originality).

You seem confident that it is a GT. Would you mind elaborating as to what you have found that is so definitive?

Thanks,

Allen

 

I have a 65 mustang 5F09A699979 that seems to be an original guardsman blue (underneath carpet and seats and inside trunk) but if GT fastbacks didn't come out until April 65 could it be guardsman blue? It's missing door data plate.

Your fastback was built on/around April 20, 1965 looking at your consecutive unit number compared to other data-plates recorded.

Also engine has casting C4OE-6015 C date code 4D3, seems to be hi-po block April 3,1964.

That is not an original engine block in your Mustang. The original would have a casting of C5AE-6015-E.

Toploader is HEH-BT (used after 2/1/65)

Both WIDE and CLOSE ratio 4-speed toploaders in '65 were tagged HEH-BT so that toploader may be original to your Mustang. If you want to find out if its a wide or close ratio you can count gear teeth to verify.

flywheel is C3OE-6830 B date 3L9. Are these casting numbers too old to be original to a 65 GT Fastback?

Engine block and Flywheel, yes!

Does your 3rd member still retain its axle tag?

What casting # and date are on your intake manifold?

If you remove a valve covers you can find date codes on the cylinder heads.

 

Well i looked again and the blue color behind the rear seat where the reinforcement panels are and under the trunk transition pan between the trunk and back window are the same color, could be caspian blue but looks more like guardsman. Guess i will never know for sure. Not one to spread rumors only repeating what i have found on this forum which is fed from fellows like those responding. Talked to an old Ford factory worker who said if they ran out of parts like steering boxes they put in whatever they could get their hands on.

Thanks to those that have responded with good info as I'm just trying to find out all i can without the original door tag.

 

The only part I ever heard of being substituted was the BW T-10 when they ran out of toploaders.

 

correct radiator support holes, original fog light switch with 'D' shaped hole in dash and original wiring all within original wire loom, reinforcement plates behind rear seat, correct rear framerails, original curved dash below speedometer in 5 gauge cluster, etc.