Hi- On the alternator-I agree with updating. I used a one wire Gm, used for maybe the last 10 yrs on chevys for example. Avail in different amp ratings and has internal regulator so you wont need your current regulator. Wiring diagrams should be available in some of the street rod websites, its simple to wire. I think I used original mounting brackets with a different belt. This was 10 yrs ago, I could be wrong. I changed to negative ground since mine is a 55, at the same time. Make sure the pulleys are in alignment. If fabrication is needed after you get the alt, and take a look at it, then get help.
With the ac you may need some help. I would use a shop that does street rods etc because they can fab if needed. I used Vintage air and some commercially available brackets. The shop will have access to them. You really have to be able to visualize to do this kind of fitting work. . Vintage Air has several sizes of the units that fit under the dash, you can get measurements from their catalog. Mine was the medium or large, but again, this was 10 years ago, products may be different now. Mine fits way up under dash and steals some of the glove box space. It comes with heat and air. They have duct opening vents available which happen to be the exact size of the Packard ashtrays in the dash.
You can buy their condenser, or have the shop buy a factory replacement condenser that is larger from some other car. They will have a size chart from which they can do this. The larger the condenser, the better the cooling and cost will be the same or less.
I would suggest that you run the trans cooling lines thru a separate cooler, preferably the larger of the two that B&M transmissions offers. You can get it from an aftermarket eqpt catalog such as Summit Racing and others. B&M has a special design that limits the fluid cooling when cold in order to help the trans fluid warm up quicker. The reason for a cooler is that the ac will put a strain on the cooling system, and running the trans fluid thru the hot original radiator makes no sense and adds heat to the radiator which it doesn't need with the added load of the ac. Plus this will definitely save your trans. Heat really kills these transmissions.
I used a large electric cooling fan in front of the radiator with a thermostadt sensor that sticks between the radiator fins. . I would suggest some kind of sheetmetal fabricated fan shroud, with half of the fan depth inside the shroud. I found a plastic one from a 70s car that used a large size fan, in a swap meet. I think its easier to make one. You may look at some 60s cars, such as 58-64 chevs. They are common. If you meet some people who have parts around, you can take your car an check it out. Or ask whoever may be doing the install. This will help at low speeds. Higher pressure Radiator caps will help, but be very careful as you have an old radiator that does not need more pressure. If you are considering one of those stainless steel fans, they are great but the center diameter is not the same as the stub on the Packard water pump. So, you would need to have the fan hole precisely machined. This does not mean to ream it with a grinder as it will never be right. The ac will make you look forward to driving the car. I would think that labor for the install would be in the $500 to 800 range, and you can price the rest, maybe 700 to 800 for parts. Shop around. Try to meet some guys who work on altered cars or street rods. Car shows are a great place to ask around.
Hope this helps.
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Hi- This looks great and the same colors as my 55. Was this car purchased from the Atlantic City winter auction a several years back? There was one there also in this color. As far as the treadle vac, just allow plenty of distance and make sure your emergency brake is adjusted perfectly and say your prayers.
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