As long as you're very gentle with the plug wires it's O.K. to trim them as necessary . Look in the operator's manual or shop manual to see how they should be grouped and routed .
The last set of wires I purchased for the '51 were for a late model Jeep Cherokee with a 4.0 inline 6. They fit very nicely, but two of the spark plug boots are different than the others.
You can always cheat and use solid copper stranded core wires and solder the ends on and use resistor typ spark plugs......
I was able to re-arrange the wire set to a very satisfactory result. My plugs are AC 45R and now with the new 7mm carbon core wires, new Pertronix coil and Ignitor - it now runs as smooth as ever. The Ignitor's info sheet states that it is not compatible with solid core plug wires, but I previously ran with the solid copper wires for years (until it died on me).
THANK YOU for the warning ! . I've never had one fail yet but I'm careful to never leave the key on when testing etc. unless I disconnect the power to the Pertronix . For me, a Mechanic/driver/owner of various older vehicles, there is NO DOWN SIDE to this )or any other) breakerless ignition system as it instantly drives the system to it's maximum output, why you get easier starting how or cold , more power and increased fuel economy all at the same time along with less maintenance ~ yes, you still need to check the timing occasionally because things wear . Never forget to OPEN THOSE SPARK PLUG GAPS as there's where the extra power and fuel economy comes from : better combustion by hotter sparks .
From what I’ve seen online some engines require a magnet that sits under the rotor and not needing the rotor I think the v8 engines haven’t seen it for the 6 cylinder
The new Pertronix I just installed does not use a "rotator" like my old one, but relies on the existing lobes of the distributor shaft. Works very well so far.
I have installed the Pertronics in my 57 and having a bit of a problem getting it to start smoothly. It was running OK before. I have statically checked the timeing following the valve train procedure that’s out there and did not removed the dizzy so it should be pretty close. Am I reading here that I shouldn’t be using solid core spark plug wires? Not sure what I have on there now but they have been there for a while. I have been leaning to the carburetor as I was fooling around with the the mixture screw as it was running to rich and may screwed it up.