Thanks, Chief- I know the chaser(s) have been around a long time... I've just never owned any because the taps worked fine.
I was taught to go by "feel" (when threading, etc) & I'm still learning. As soon as I got somewhat proficient with tapping/threading holes into new steel I started working on this old truck. I am having to relearn a certain finesse & "feel" with its metal as well.
Brad