New '63 owner and a few questions

[Sledgebone]

Hi everyone, my name is Robert and I am from Michigan. I have been a fan of this style of truck for years and just picked one up locally to replace an '88 C1500 that was past the point of fixing.

I wanted a driving project that I could work on slowly and preferred the 60-63 style with the wrap around windshield. I wasn't into driving a ways to pick one up or have one hauled to me so I was keeping my search fairly local. This one came up and I looked it over, drove it and made a deal. I paid a little more than I felt I should but the owner didn't want to move much and after some very serious health conditions in the last year, some things just don't matter as much as they used to.

The body is very straight with very little issues. The floor pans need to be replaced and there is a little rot above the driver's side windshield on the inside. I am assuming the brow will have to be replaced as well. It's got a 230 3/speed which I was told was original. It runs great, goes straight and stops.

I have just a few questions.
- What is the middle dash knob for on the left of the steering column? There is a switch but wires are absent.
- My old truck is going to get hauled away by the scrap yard soon. Is there anything out of that truck that I should salvage? I plan on doing disc brake swap but would like to do 5 lug. I believe I could use some parts of that if I wanted to stay 6 lug. I also plan on rewiring the '63. Is it worth it to pull the box and harness out or buy a simple kit?
- Where were the original drain holes in the drip edge? Mine seem to have been filled.

Pictures in the next post.