How to check Trans fluid on 71 280SE
 

Hello all, Can someone tell me what type of Trans fluid this car takes and exactly how to check it? It is a 2.8 FI motor and the trans is a 4 bolt pan tranny.. It says on the dip stick to check with car running but I just wanna make sure that it dont have to be in gear.. Sorry if the question seems stupid..its just that I dont see anything on the dip stick with the car running and in park..I will add if necessary but dont wanna over fill it..I am looking for a service manual for this car still..I just ordered a tune up guide.. Thanks for your time and your wisdom..:)