What tranny?

Now I know that my 727 will not work because its a push button tranny. So now Im looking to use my 904 that came on my 318la. The dip stick tube has been out of it for about 13 years and its filled with crap. The input shaft is rusty, Im not sure how bad it is. The fluid is nice and red. Thats about all I can think of now, what do you guys think, should I drip the pan? Also soon I hope to drop this engine in. I have never done this before so whats the steps you guys recommend.

Thanks
Evan