Here is my "scale model" of the Little Joe II, which was used to test the escape tower for the Apollo program. It has a corrugated body, just like the original. Sadly, this version is liquid-fueled, unlike the original, and some of the construction may seem odd, but I built it with scale appearance in mind. Ooops... I notice now that I seem to be missing the other three RCS quads. I'll go fix that now (but the pics shall not be changed).
It has an engine configuration similar to flight A-004: Four large motors, and five small motors arranged with three of the small motors in the center and two further out. You can see the small solids burning in the liftoff shot below.
Below we see the rocket apparently having control problems... like the real one did on occasion. You can see the RCS thrusters firing on the SM and by the fins.
You can use the abort control (or the Backspace key) to initiate the abort. I also have it on Custom action grouping #1.
The capsule is pulled to safety. There are a couple angled motors on the tower to veer the capsule away from the booster's path.
After the escape motor burns out, you can press spacebar a couple times to release the tower. But Custom #2 will release the tower and fire two more motors on it to pull the tower away from the capsule.
Another press of the spacebar will pop your chutes. I also have that on Custom #3, just so you can do an abort nicely with: 1# ... pause... #2 ... #3.
And the crew capsule descends safely to the ground.
In the course of a normal launch, I have Custom #4 set up to jettison the tower by itself under full power when you don't need it anymore.
If you wish to recreate those amusing Mercury days, you can press Custom #4 while on the pad to launch the escape tower.
"Ah ha!" I hear you saying, "Does the escape tower have enough oomph to pull the capsule to safety from an explosion on the launch pad?" Indeed it does! Below is a pad abort sequence. All it needs is a giant fireball on the pad to make it complete.
Now what we need are Action Grouping commands that would allow you to build in delays between executed actions.
Additional: OK, I couldn't resist exploding things on the pad so I could try to snap a good picture of the capsule escaping from the blast. Who'd have thought it would be hard to get a good picture of an explosion in KSP? Anyway, it involved a lot of dropping the rocket (with some extra tanks attached) from some launch supports. And it involved repeatedly scaring the crap out of Richler, Ferden, and Enbles Kerman. But here are a few pics below: