Terrible starter problems

So, hello I’m in Santa Fe New Mexico. I have an 02 4.7l and was pretty sure I had a bad starter as it just suddenly started stopped engaging. I know I have badly corroded cables and have been mitigating that as I can. Pulled the manifold put in a new starter and checked trigger line which was at well over 12v as was the main power. I had alredy Checked and replaced the relay. After delays of swearing and bitching I checked my continuity from the main starter power and ground and got very an open circuit signal. I also got an enormous power drop to the main starter power when it was triggered.
Anyone have any good experience replacing the power line to the starter?

 

Welcome from LA (Lower Alabama)! You will get a lot more response to this if you post your question in the 1st Gen forum:
https://www.tundras.com/forums/1st-gen-tundras-2000-2006.2/

Or in the Ask the Toyota Mechanic thread:
https://www.tundras.com/threads/ask-the-toyota-mechanic.2404/

 

Welcome from NY.