have an 82 351w that has the dreaded ecc iii dizzy-----timing totally controlled by computer. wish to simplify and go to a ford version hei, but when i got my dizzy it had 1/2 inch shorter shaft than dizzy i pulled. my original dizzy is approx 5 1/2 inches from end of shaft to o-ring------but new one is approx 5 inches. by my measurements, the shaft would overlap the oil pump shaft by about 1/2 inch with the new one. is this enough overlap? does anyone have a dizzy they can measure and see how it compares? thanks for any help offered!