I dislike those retrofit setups immensely.. They use that heavy bulky corvette master and a booster and bracket that is extended way away from the firewall. Your brake lines end up nearly up to the end of the valve cover.. This setup was installed on my 56 Vicky when I purchased it.  I ripped it out and replaced it with a booster from a Ford ranger and a mustang master cylinder.  Much tidier setup

The ignition wires are normally tied back to the brake lines under the MC, but it's a fairly messy arrangement. I've taken your collective advice and have started to reroute them. It gets fairly busy down there, particularly with all the header pipes.

The MC is part # CAL-4478 and the booster CAL-4483 from https://performancewarehouse.com.au/

That looks like a good fit.  What are part numbers for the booster and master cylinder that you selected?
Thanks!

Paul is right. You may want to tie those IGN WIRES down as they are routed over the exhaust manifolds - 

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"New 7"double diaphragm unit in place. All seems to work well. It requires a little more push than the old one, but quite acceptable".

"18 at idle out of gear 770rpm. 15 in gear at 620rpm"

Well, there may be a problem (don't let me get you worried).

It takes @ a minimum of 18Hg to properly operate a booster @ all times (to keep the booster fully charged) and that also is considering the brake type, MC bore size and pedal ratio. 

The vacuum tank portion can only hold what the engine gives it in Hg. So say the engine only supplies 15" @ idle (in gear) manifold vacuum. It (vacuum canister) may not recharge itself (with low vacuum supply) enough for several back to back stops @ speed (the pedal becoming harder to push).

But this is less likely a hindrance with four wheel drum as they are self activating (not as much line pressure required as disc). Once the primary shoe makes contact, you will then have full brake application.

As long as you are satisfied with it and the pedal feels good, I wouldn't worry too much. It is the multi-stops that may get to you but you would still have manual application requiring a heavier foot. 

An exercise if you wanted to know for certain is to tape a vacuum gauge to the windshield and see what vacuum the engine supplies at differing RPM's while driving.

If too much vacuum or too large/strong a booster, you may get the touchy pedal syndrome to whereas it wants to throw you into the windshield. It is all a fine balance.

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18 at idle out of gear 770rpm. 15 in gear at 620rpm.

If you can, running those spark plug wires like a stock yblock might give you more room.

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Vacuum comes up to 17 or 18 with at about 2000rpm.]

What is vacuum @ curb idle (AT in gear)?

Nice looking install.

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New 7"double diaphragm unit in place. All seems to work well. It requires a little more push than the old one, but quite acceptable. And the valve cover clears easily now!

I guess it would be best to leave as is if it is working correctly. If you loosen the booster/MC assy, can you somewhat slide/tilt the assy over to clear rocker cover removal without disturbing the brake lines too much? ? If not, the only cost effective choice would be a double diaphram booster.

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