About 1989, I modified a Centuri 1/45 Little Joe-II with an A3 engine mount intthe base of the Apollo CM.
A mercury switch system caused the A3 to ignite at burnout, pushing the capsule (with LES) off from the Joe body, and boost ahead of the Joe. It worked well.
And around 1992, I did the same for a custom built boilerplate for a 1/39.5 scale Little Joe-II. Using a C6-3 in the base of the CM, using rear ejection. That also worked well. However I chose not to do that with a contest model.
In both models, there was a custom-made short piston, using a tube that was an easy slide-fit and plywood disc. The electronics were mounted into that piston. After install, with model on pad, the system was armed and Apollo CM/LES carefully slid into place.
Yeah, so it's, not "scale" like. BUT, it worked well, and LOOKED good as the CM/LES thrusted away (at 200-300 feet up, where it would be hard to see exhaust of a wimpy motor in the tower).
Also, by pressurizing the base of the CM and "popping" off, that solved the problem of getting the capsule to let go. It would be terribly difficult to have a wimpy motor system in the escape tower, that had enough pull to yank it free from the Joe body, without being so loose it would likely slide off at burnout.
The "easiest" fix I figured to solve that, would be to fire a "separation" charge inside the tube, between the piston top and capsule base, at the same time as the LES motor would be fired.
Below, my old beat-up 1/45 Little Joe-II (dozens of flights), modified for a 7-engine cluster, and the "Abort" A3 system for the CM/LES.
