I had one in my 40. It worked great, I ran a larger gap and never fouled any plugs, etc. It's nice to get rid of the old ignitor stuff and just have 1 wire going to the distributor. Plus, these use GM HEI parts so they are available any where if something ever went bad.
Randy Rosetta KDØKWX TLCA #19351 69 FJ40 "Meanie" & 1970 Boss 302 Mustang