A518/46RH transgo TFOD-HD2 shift kit install

I believe that was only in certain years, can't say for sure which years though, any trans I've pulled apart from '88 and under hasn't had the small spring. I would discard it and keep just the piston and the spring in between it and the valve body.
My tranny is from an '89 Dakota. Anyway I won't worry about it then. Thanks