If you look at ebay or similar and enter "Deutsch connector" you will find a variety pin numbers of well-insulated and waterproof connectors. I used these on my L35 when I remade the electrical harnesses and recommend you get the "pigtail" variety using 14 ga wire which will usually be larger than the OEM. However if the wire is handling glow plugs or high draw circuits, you will see they are likely 12 ga wires and probably have their own single connector.
The Molex type connectors you show are sort of typical on many machines, but they aren't waterproof. However some dielectric grease helps unless you are constantly pressure washing your wires
Some of these connector kits have you make up the pin/wires and then insert into the plastic connector. Yes, I've done that too on previous restorations, but a lot of work.
I'm not fond of bullet connectors, but I did succumb to using them on lights. Likely you can find these in an automotive parts store.
The metal in the Chinesium connectors is crappy and very thin so you kinda have to be careful.
You can also look at Mouser Electronics and Allied but I think they're pretty expensive over there. I've had no luck locally and had to order everything.
And don't forget, if you have OEM 10 contact connector as example, you can always use 2 5-contact connectors.
I see you have a multimeter, therefore I assume you also have wire strippers and crimpers? Handy to have. Beats a Bowie knife and scissors! I'm anal about wiring so I tend to solder everything anyway.
Before I forget, if you peel back insulation and find green or black corrosion on the wires, better to cut it back until you find good copper. If bad enough, the corrosion will eat the wire and well....
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Also you can search on "automotive electrical pigtail connectors"
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