The electric choke conversion power supply should (IMO )be sourced directly off the BATT via a relay (IGN SW activated) and fused and in no way sourced off the IGN CIRCUIT..

____________________________

While I have not experimented directly in putting 6 volts to a 12 volt choke coil, I have seen instances where the choke was hooked to the positive side of the coil on 12-volt systems.  While the choke did work, the drop in voltage to the ignition was a problem which is where I become involved as the cars are either hard starting or experience a misfire at speed.  Part of that warning about using a minimum of 12 volts is to eliminate installers from using the positive coil connection for the voltage supply.

If hooking up a twelve volt choke coil to a direct six volt source (ignition switch), there’s no doubt in my mind that 6 volts would simply have the choke coil open more slowly but would still open fully.  On the flip side of this, there are lower voltage electric choke coils available which would speed up the choke operation in lieu of using a 12 volt choke coil.  Considering how fast the electric choke works when using 12 volts, I suspect using 6 volts on a 12 volt choke coil could potentially work better in that it would slow down the opening of the choke.

Lorena, Texas (South of Waco)

INQUIRE HERE - https://www.carbsonly.com/Graphics/BigPicks/electrcichoke7v.htm

____________________________

Daniel....all of my cars are still 6 volt positive ground.  One of them has a more "modern" Holley 4 bbl carburetor with an electric choke obviously designed to run on 12 volts.  I too, doubted that the electric choke would work on 6 volts but it does open which surprised me so I have left it alone.  

6 VOLTS/POS. GRD. NW INDIANA

The Top Street Performance (TSP) intake manifold is the twin to the Mercury 8 Restorations (M8R) manifold and I’ve had both in the shop.  Neither of these manifolds were machined for the factory heat tube to accommodate the 1957/1958 automatic choke but not a big deal for that as Ford discontinued that particular heat path and in 1959 went instead to the right-side exhaust manifold for the heat source for the choke.  In most modern intake/carb conversions, the electric choke is the method of choice for the automatic choke which removes having a heat source at either the intake manifold or exhaust manifold.

In both the M8R and TSP manifolds, I found no additional holes, threaded or otherwise, that were not already in the factory ECZ-B manifolds excluding the drilled choke passage that went from one side of the ECZ-B manifold and to the other.  In running the M8R manifold on the dyno mule, it made the same power numbers as the factory ECZ-B intake manifold so it was a very good reproduction of the factory manifold.

Here's the link to some additional information posted last year on this site regarding the M8R manifold.  Doing a search will find some more.
http://forums.y-blocksforever.com/FindPost168994.aspx 

Lorena, Texas (South of Waco)

The Hot Rod Reverend did a video, which is a bit painful to watch, and he notes the absence of holes for the heat tube.   Maybe the seller on FB tried to add one and then sold it.   

Someone who recently purchased a TSP manifold posted on Facebook's Y-block Group. He was under the impression that someone was careless during manufacturing and drilled unnecessary holes in it. He said that he was going to use J-B Weld High-Temp Putty to fill the holes. Based on his photos, I concluded that the holes were deliberately drilled to accommodate the heat-riser tube that passes through the manifold and would have the mushroom cap on the passenger side. Does the TSP manifold include the tube?

I just bought one direct from TSP for $189, free shipping.   I used the 10% off WELCOME10 code.    

Link to the Reverend’s write up:  
https://www.hotrodreverend.com/post/brand-new-1957-four-barrel-aluminum-intake-manifold-for-the-y-block

Ted also weighed in last year about this manifold:
http://forums.y-blocksforever.com/Topic169098.aspx

Link to TSP:
https://topstreetperformance.com/products/1955-1957-ford-thunderbird-4-barrel-4v-aluminum-intake-manifold-ecb-9425-b-272-292-312-satin?_pos=2&_sid=6faa32b74&_ss=r&_fid=a41d89132

Heres the company:

https://topstreetperformance.com/products/1955-1957-ford-thunderbird-4-barrel-4v-aluminum-intake-manifold-ecb-9425-b-272-292-312-satin?srsltid=AfmBOorUiLeJK8DjsNfhmaLS9fYP8-Pm-8PtDFVTDQewsVEs9fSWMc-6

I've bought a couple of them to have on hand. Its basically a direct copy of a B manifold but half the weight and typically, almost half the price.

Free shipping and use "WELCOME10" for 10% off your order.

Mr. Jessup did a nice write up on his YouTube channel. Theres a little port mismatch but nothing that I personally would be concerned with on a street car, barring a vac leak. A little enlarging of a gasket bolt hole would alleviate any anxiety on that front I would think. I don't know if anyone has actually installed one on a car yet as of this moment.

https://www.youtube.com/watch?v=fywiDDVKVhg