Need serious support for 722.3 transmission rebuilding

[werminghausen]

My W124 400E transmission gave up, it acted up and I found lots of metal chips in the pan. I decided to rebuild the transmission myself, want to be brave.
The idea is : I 'll install another used transmission that I bought on ebay and then I will rebuild the failing transmission. These are 2 separate projects really.
project#1: getting the new donor transmission ( 150K miles) re-sealed and change the reverse friction disks+ flush the cooler.
Proactively I bought a Precision banner kit 68004B for the 722.3, I believe it includes all seals, gaskets and 3 x 5 Allomatic frictions K1, B3 and K2 for .
I got the donor transmission rel. cheap and the first question is: does a product like Precision make any sense or does this call for future pain if seals and disks suck in this 'aftermarket' set?
Alternative frictions would be Borg Warner, still aftermarket but seemingly more expensive but also better? I'd need recommendations regarding the quality of available banner kits or master kits (master kits have in addition to the banner kits also the steel disks).



Second question is about flushing the cooler: with chips in the pan of the old transmission ( I guess some spring has been eaten by the tranny) how great are chances that the cooler is contaminated? I guess if the pump itself is not damaged and eaten alive and the filter worked then no chips should be found in the cooler... but I might be wrong. I am planning to flush the cooler with alcohol (ethanol) and shop air.

Any suggestions are welcome as I have the donor transmission her and will start resealing soon to get it installed in the car and hopefully drive.

Project #2 will be the rebuilding of the damaged transmission and this will be the real deal and challenge for me as soon as the car is on the road again and i have some piece of mind for focusing on the total rebuilding.
Again any help is welcome for project 1 now

I have a car lift and a transmission lift..all basic tools and some experience in hydraulics...but never opened up the transmission.
Martin