M_Boats: headstay

Help!!! I am in the process of buying all the stuff necessay to fit a CDI furler to my M-17 "Little Breeze" (hull #265, Aug. 1977). At present, the boat is on the hard with the mast down. Measuring all the existing forestay fittings (swaged stay and tensioner) I came up with a pin to pin (masthead to deck plate) length of 22ft-9-3/8in. Originally, and as used for the last few years, the boat came with an adjustable forstay tensioner instead of a turnbuckle. How does that measurement compare to other M-17's and have they changed over the years......"Little Breeze" is a sweet 30 year old. Am I missing anything here and/or has anyone had problems with this conversion? Hangten---Arnold Sharpe