I believe the stock tach is configured to four cyl only.
You are gonna have to spend a few bucks on a tach.
But Jonny.....do you really need the tach now.
350 , turbo 350, you might not miss it.
Most of us cruiser people have no tach to begin with.
I think there's some way to jimmy it up but the question is, would it be at all accurate? An aftermarket one is the better way to go if you're going to be watching for that redline (with a standard tranny).
'86 Toyscrota, currently in too many parts to count.
the tack is more or less for my curiosity than for any real purpose as I will be running a th350. and I fuigured since it is there I might as well see if I can hillbillyize it so that it works. if not no huge loss.