Re: 22 1/2 inch shift rod for 1978 mercury 70 hp long shaft?
If you look at the Outboard Motor Shaft Length diagram and do a measurement from the top of the transom to the deepest point of your transom and it comes out as 20", then you have a long shaft motor and you would select shift shaft p/n 75355A32 which is for a long shaft motor.
I just looked at your previous posts and you said that the shaft you are looking at is from a 115 hp. Be careful and don't waste your money by using the length, use the p/n. Do you know the s/n of the 115 engine?
You still haven't posted the s/n of your engine. Do you have it? If it is a long shaft, here is a shift shaft on ebay: