Power piston length is 1.950 with.340 o.d.,believed to be factory unit, I bought your white retaining repair bushings earlier. Don`t fit bore on 67,s.. I also bought steel sleeve that goes around power piston bore to hold down power piston. When installed power piston is coming up to far and with new metering rods I just bought from you are coming out of the jets. I know there was a metal sleeve that goes downinside with power piston. I don`t have one. What should I do to make it work.