A Florida newspaper did a really good long read but it's behind a pay wall now apparently, so I found this copy of it posted on a forum for you. While there's some detail missing from more in depth articles and books on the Brabant Killers, it's a really good overview of Jean Francois Buslik's life, decent on his and police links to right-wing terror groups, and at least references his father's work for the CIA and other possible intelligence connections talked about more elsewhere.

The aviation school where he was head flight instructor was called Kemper Aviation and is well known and sourced as one of the ones used by thr 9/11 highjackers to train. For example, here's a reference to it right at the start of a Newsweek article.