I've seen worse fuse box clips. If that was all I would say try to clean them up. The little brushes from electronics supplies and De-oxit work decently. IMO the weakest locations tend to be the wire crimps to the terminal.
This guy
found some fuse box clips on ebay. I bought some from Evans and used ones from otehr FABO people.
Ammeter red wire pulled out the firewall connector. Is the barb on the terminal damaged or is the plastic damaged? Definately don't want that (or any) terminal backing out when the two connectors are put together.
if your OK with not 100% original, then one work around is to copy a '60/65amp' 'fleet' option wiring. You'll want a good grommet (and a positive locking connector if you do a connector). If you're doing that, then add a second alternator output wire as well. That's the wire that sees the highest currents.
I can't speak to hiding an MSD. It needs to have a very good and relatively short power supply circuit, and reasonable cooling.
Below is what I did on my '67 Barracuda. I used the factory grommet and single stud terminal locations. MSD joints at that terminal. MSD on/off is joined to the original run circuit that originally connected to the coil positive. Ballast resistor connects ignition run and start circuits (no change).
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The R6-12ga Black is the original standard alternator output wire.
The added alternator output wire connects at the terminal stud.
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As yours is a '68 it uses a different bulkhead cavity location for the A1 (battery feed) and some other circuits.
Since the battery feed was in relatively good condition, I did not run the battery feed through the grommet. If it wasn't, I would have. Make sure you put a fusible link in. Here's a diagram of one way that was done on '73 B-bodies exacept with two fusible links (one for the 6 gage wires and one for the 12 gage wires)
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The assembly drawings show the same concept as a '68 A-body option. I don't know if any were actually built.
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I think the terminal block should have a third wire on it as shown in the '73 diagram above, or the fusible link at the starter relay should be 16 gage (blue).
Here's the firewall grommet and wires on a Swiss export '74 A-body -uses a simialr concept although slightly different execution.
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