With hogs gestation period is the rule of 3 3months 3 weeks and 3 days so ifyou know the day of conception you can say its roughly 103 days till farrowing
JD 2350 they only made them for three years from what I can tell- 1983-1986! I love it, it’s the best tractor I’ve ever had. I would like to see your dad’s tractor!