Chris Craft offered the "F" series engines (283 F & 327 F) in Commanders from 23' to 35'. There are a lot of these engines out there, and they have a problem. Most of these engines were equipped with IBM Prestolite 4115 distributors. Unfortunately these "flat cap type" distributor caps are no longer in production and are virtually impossible to find. It was still listed in some marine supplies and places like NAPA, but they were incorrect. The original cap was a higher than normal flat cap that had been problematic in the past, just as the Mallory flat cap on 427's is problematic.
 Here is a tested solution – The Distributor Cap Modification Kit modifies a commercially available Sierra 18-5369 cap and uses an unmodified Sierra 18-5407 rotor so that they fit on your 283F & 327F engines with Prestolite 4115 distributors. This cap is not a flat cap. It’s a stack cap with wires coming out the top of the cap.
 
 Kit Includes 2 spacers, a cable tie, installation instructions, and Shipping & Handling.
Modification kit does not include cap & rotor. These must be acquired separately by purchaser. Each kit modifies one distributor.
 
See the installation video here