As for the Redstone dropping it's tail section, if true, then someone will need to revise his rockets book.
Sigh.
Not true, not true, not true.
Movie got that part wrong, wrong, wrong.
Realize, i'm not writing this based on interpreting info on the internet, poorly worded wiki's and all.
"its on the internet (or in a movie) so it must be true". Nope.
I know this beginning from when I was a kid and remember seeing Alan Shepard's launch on TV and following the space program closely, thru researching the Redstone (focusing on the Jupiter-C and Mercury Redstone versions) in the 1980's when I researched both, in a lot of detail, as I was working up to build one of those as my first really serious scale model. I ended up doing the Jupiter-C (known later as Juno-I when it launched Explorer satellites), mainly because I could not work out a good way to do the dimpled pattern detail on the Mercury Spacecraft. That's one of the reasons why I looked inside a Redstone to notice the chain and sprocket assembly, I was literally crawling over it to get data and dimensions. See photo later of some of the data gathering.
Page 205 of Alway's Rockets of the World, about the Jupiter-C (Juno-I), among the Sources credit he used for his work are drawings I made which were printed in the January 1988 issue of American Spacemodeling magazine (Name of NAR's magazine at the time, now Sport Rocketry).
The 4" North Coast Rocketry kit from the late 1980's? That's not me with the NCR kit below. That's my model that NCR cloned the nose section of to make a mold for their kit. It wasn't a detailed model, actually, didn't do the 3.5" gap between tail unit and tank, or any surface detail or the antennas on the Instrument Unit. I built that one as a "sport flying" model for the 30th anniversary of Explorer-1. But I did have a lot of data and did make a smaller (BT-80) more detailed contest model but do not have a photo of that one. Still, the project ended up being modeler-limited, it was not data-limited - I know a lot of stuff about it but knowing and model building are two different things.
A friend, Randy Kelling, helping to measure the gap between the Tail Unit and the Redstone tank in the photo below, around 1985 or so. I rigged up a pole with rulers at 90 degrees to assist measuring things too high up to reach. In this case, used binoculars from farther back, at a better angle, to read the vertical ruler more accurately for the gap distance. Those twenty threaded assemblies connecting the two, were not explosive bolts. They were attached and detached using human-operated tools.