Yes, I am talking about going that slow. When a highway turns into a mountain pass with slow turns and steep grades, something we see out here in the west quite often.
Pull over at the top of the pass, pull OD handle out, proceed... Did that many times in my Ford with an R10.
Not to say I didn't love the R10, I did. Just noting a downside depending on your geography. For some in the flatlands it will probably never be an issue and I always thought of it as part of the charm.
If I was retrofitting a different trans into a driving (done?) car I would pay the extra $$$$$ for an R10, if I was building it I would put something better in it (T5 / TKO). Either way, I really wouldn't care that I modified it. No stocker is ever safe in my garage