There are a couple of people working on them:
These are boats prior to the stinger in 1975. Which has the better porting, tuner and the nitro case.
The hp ranges from 55 to 65 depending on the year. They were all large gear case models. Low 50 mph boats.
Dave is building a 14 Checkmate: He was looking for the old 15 mid.
Dave here is one:
https://www.kijiji.ca/v-powerboat-motor ... nFlag=trueI have a nitro case with a 2 cylinder gear set and a 15 inch course spline 3 cylinder drive shaft. I would like to try it on one of these boats.