Drain the pan, replace the filter and button it up. Next open the access panel on the front of the transmission and drain the converter, there is a little plug on it, you will need a 5/16 wrench or 1/4 inch wrench for this.....
I would also drain the differentials and refill with fresh fluid...the dana 44 front is easy, just remove the back cover and the fluid will drain....clean the cover, fresh gasket and then refill it...
the rear 9 inch is a lot different..in order to drain it you have to remove the axles and then the center section...it is heavy...if you don't have a lift or you are doing this on the ground, i wouldn't advise it, take it to a shop and let them do it.
once this is all done, you will need about 11 quarts of trans fluid, use mercon instead of type f...fill the pan with about three, then have the rest open and ready to our once the engine is started....you can start the engine with a remote if you are by yourself, better to have a friend though. double check the manual for refill spec's...then as thge engine is running keep adding the rest of the fluid till your trans is full, check the dip stick after about 8 quarts/ pints, again what the manual say's to fill it with.
On mine i added lucas transmission additive to help clean the internal clutches and valve body to help improve shifting...

hope this helps

 

that helps alot thank you. my haynes says the transmission can hole 11-13 quarts so i bought 3 gallons. i already did the rear 8.8 with clean diff fluid im in the middle of rebuilding my front axles so i will do the TTB before i put those back in.