Im restoring my truck and I had oringinaly planned on replacing the factory wiring harness but it still looks like it is in good shape. I checked all the connections and found no problems.

Would you recomend replacing it just because it is old or do you think I could get away with cleaning it up and re-using it.

I personally think the whole aftermarket harness industry is one step away from being a scam.
If your harness is fine, or only needs a few small repairs, use it.
If it looks like a family of mice has been building a condo in it... it's probably a good idea to replace it.

I really doubt that the replacement/aftermarket for wiring is a scam, the materials used in todays insulation is far superior to that of 30 years ago.
If you harness is in good shape, use it. If it has been cut/spliced/damaged beyond repair and you wish to replace it, so be it....The most important thing is too keep moisture out and the connections tight and in good shape.
I really like the "TXL" wire such as painless wiring supplies, the insulation has extremely hi heat resistance and is light weight.
You can do anything with wiring.....and if you compare todays wires with that of what came with these trucks, there is no comparison.
This is my opinion and nothing else.

My initial reaction was that I kinda agree with Longhorn Man for what I think are the same reasons, but I also sympathize with BubbaGreen about the newer wires being lightyears better than the old stuff.

I think the separation point is that a lot of the original wiring harness used molded plugs and individual harness sections that fit right. Also, splices and universal crimp connectors are non-existent which helped these harnesses survive for a long time.

On the other had, damage to a wire sometimes cannot be readily apparent. Strands may break inside of the insulation, slight overheats could damage the conductability (I know that's not a word), and a whole host of other things could go wrong.

So, my recommendation would be to test out each component and wire to make sure it is good. Inspect every inch and every connector (use a multimeter and measure the resistance of each wire). If 75% is still good (and you don't have plan to add a whole lot of additional accessories) use the original. You will still be able to get whatever replacements you need from either M&H or American AutoWire for less than what an aftermarket kit would cost. And it will be a whole lot easier to install.

Thats what I wanted to hear..Thanks for the help!!

if its in good shape with no cracks in the insullation use it// if you're going with hei ignition you will need to open up the harness to eliminate the resistor wire and install a new feed for the dizzy you'd also eliminate the yellow wire from the starter to coil