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Discussion Starter #1
So I thought the car was all original except the exhaust and wheels. Now after having a couple guys look at it, I think the paint has been redone in base/clear and some of the rubber and window felts have been changed. And the master cylinder is not original. I hated the 3.90 gears as well so I'm going to put in 3.36's which, according to the shop, will allow me to keep it a posi. He was thinking about non-posi 3.23's. Better than the 3.55's he was originally suggesting. Hope there's not much difference, but I don't enjoy taching 3200 at 55 mph. Am also going to replace the non-original non-power master cylinder with an original restored master with a mid march dated brake booster. Car sold mid May. It won't match what's on the build sheet, and I can always look for a correct one later, but it'll make for a safer, nicer brake system. I'll keep the gears so when I croak and my kids have no interest in the car, they can get a little more for it! Now I have a complete set of redlines and just need to finish painting the 14" Rally IIs. Last thing needed is a set of trim rings. Have a set that came with the car, but they are not the correct ones. May use them in the meantime.
 

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If you make changes that improve reliability and safety, I'm all in.

First thing i install on these old cars is HEI, internal regulated alternator. Then move the fuse links off the engine to a serviceable spot and install a ford starter relay.
 

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Discussion Starter #4
Didn't intend to come off that way. Just that once I started finding a couple non-original things, it made sense to do a few more to make it safer and more liveable. Got the Rally II's/redlines on now. Next week the gears, back to stock rear springs, and new Delco Shocks to replace the spirals on the back.
 

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Gotcha. I recommend replacing the rubber insulators on top of the coil springs when you do that installation. Just my opinion, but I really like KYB shocks. They will cost you a little more than Delco, but worth it. Regards, Matt
 

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Rest easy, Mike. I made the exact same gear change with my '65 that you did. Your mechanic knows what he's doing: a 3.36 is the tallest gear that will fit in your 3.90 4-series carrier. To install 3.23 gears, the whole carrier would have to be changed. Not advisable. In addition, the 4 series carriers are usually 4-pinion, and a bit stronger than the 2-pinion carriers. With 3.36 gears, you will still have excellent performance, but be able to cruise 70 mph at about 3000 rpm or a bit less. And you'll also pick up about 4-5 mpg on the road, too. It's the smart thing to do. As a side note, you can install 27" tires on the rear, and the 3.36 will become a 3.23....a lot easier than buying and changing out the carrier assembly!
 

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Discussion Starter #7
Thanks for that bit of reassurance. I did get a new set of coil insulators and now have two sets of rear springs to choose from. They are definitely not the same. Someone lied to me, but I'll return the incorrect ones. Machine shop installing the 3.36 gears. Like you said, I'd be able to keep what I have in there and not have to change the carrier. 225/70-14 tires all around. Guy knows the car as he put in the springs that are in it now. Small world. Have a set of unused front KYB GR-2 shocks that came with a previous car. Tempted to use those and get new KYBs on the back, but will probably go with AC/Delco as I'm not going to drive it much anyway. Car still has clean original spiral shocks on it. And they seem to still be doing the job as intended. No noticeable bounce back there. Looking forward to getting the shocks, springs, and gears all done. Hope to do it next week when we get a dry day.
 
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