Freshen up a 904 in one weekend. Doable?

I'm real tired of my trans leaking like a sieve and its crummy shifts.

So I ordered myself a TransGo tf3 full manual valve body kit a week or so ago. I was planning on finding a second 904 to rebuild and modify but I'm wondering if that's even necessary.

The main problem is that the Dart is my DD so I want to keep down-time to a weekend.

What do you guys think? Is it realistic to think a 904 can be pulled, torn-down, rebuilt, and have the tf3 done all in 2 and a half days?

Also, I've been looking around at rebuild kits but I'm getting a little confused in the variety. Any suggestions for a parts kit that will have everything I need?

The transmission is original to the car. 74k miles and 43 years. Suggestions on what needs to be replaced and what doesn't?

I don't need it to be built up for the strip. I just want it reliable and not leaky. But I am definitely open to modification/upgrades if it's a matter of a little extra cash gets me a better end product.

It will be bolted up to a recently built 318 but it's nothing crazy. Just a little more compression and an rv cam.

Thanks in advance for any guidance you can offer.