They will work for a vss, if it’s a sine wave generator they work. I got one for Ethel I never used from Dakota digital. You’ll have to prob have someone go in and setup your pulse counts so the trans shifts properly. You are deviating from the std 40 pulse tone ring so it will have to be adjustedI do have this, not sure what it is to be honest. It appears to be just a speedometer adapter to a electric gauge, I don't think it will work as a vss.
http://www.marshallinstruments.com/products/9220.cfm