Sometimes I'll leave the hubs locked on my '75 K/20 in 2WD. 90% of my driving this truck is off road, no asphalt. If it's bare dry pavement, I unlock the hubs. If it's just sitting or driving on wet or icy pavement, I'll leave them locked.
I have one that I bought new for my 1975, unfortunately, the snorkel on the air cleaner housing is in the way. You can have it for the cost of shipping. I may have bought two, if I find the one still in the package you can have that one. They are both chrome. I'll go look for them. Let me know...
In my experience, baking soda and water mix will neutralize the corrosion, do it a few times, overnight soaking the clamps is the best. After 5 years, I buy new batteries, period.
Mine was just basic maintenance. I just replaced the original fuel hoses on the fuel pump, 47 years of service. Thought I had a coolant leak when I looked under the front end but popped the hood and there was fuel pumping out. Good thing I wasn't out off roading.
I've always replaced the nylon cam gear with a steel one and new chain. The last one I did was on an Olds 455, it was a double tooth set. I wouln't do nylon on anything. The 455 had a lot of slop with only 80,000 miles on a 1972 455.
A buddy had a 402 in a '70 Chevelle, he stripped all the teeth...