Chrysler's later transmissions were based off the original 727.
The later 618 pan was deeper than the 727 pan but is a direct replacement.
The pan gasket was also updated to a reusable bonded gasket.
All parts used are avail on Ebay or Amazon.
Increasing the fluid capacity helps with the cooling which extends transmission life and it helps with operation at extreme angles for us that actually use 4wd.
So let's get started.
Standard 1/2" bolts and the pan is off.
I always leave one bolt in and tight along the rear so as it is loosened the pan will tilt fwd to help control the mess.
Put a big piece of cardboard down before you start.
If you have more than one drip/drain pan, use it.
Remove all the bolts but one on the rear.
As you loosen it the front of the pan will drop unless it's glued on.
Continue to loosen it until most of the fluid is in your drain pan or on the ground.
Then remove the rear bolt.
There are 3 phillips screws on the filter, unscrew and remove.
Note the direction of the filter and screws for later.
Now is the perfect time to adjust the bands and if you're feeling froggy, adjust the line pressure regulator up a little.
I backed mine out an additional 1 1/2 turn.
An even better option would be to just drop the valve body and install the Transgo TF-2 valve body kit and new shift shaft seals(2) to stop the annoying leak when the scout is setting in the drive way parked.
But those items will be discussed in future write ups.
Band adjustments are listed in the factory manuals and all over the web.
Here is what I do, may not be what your reference says...exactly.
Rear band adjust is internal.
Adjustment is 2 1/2 turns out from snug.
So loosen the 11/16 jam nut and back it off.
Turn the adjustment all the way in until contact and then go until you feel tension using a small 5/16 wrench.
The books call for using an inch pound torque wrench but I doubt many have one.
Then back the adjuster out 2 1/2 turns.
Hold the adjuster in place and tighten the jam nut with a wrench.
Now move to the front band adjust.
This one is on the outside just above the kick down lever.
I remove the clip off the kickdown and move it out of the way.
Then I use a 3/4" 3/8 drive deep socket to loosen the jam nut.
Then back it off and run the adjuster in just like you did on the rear band.
Back it out 2 turns.
Now here's the tuff part.
Using the socket prevents you from holding the adjuster, so if I can't use a wrench to hold the adjuster while using a wrench to tighten the jam nut I will back the adjuster out an additional 1/4 turn and then use the socket to tighten it down.
This is because the adjuster will turn with the jam nut as you tighten it.
Now grab the new filter and extension and pre-assemble.
If your extension came with short and long screws, use the short ones.
Then install and tighten screws.
Now clean the pan rail with some brake clean and make sure there are no scrapes or burrs or old gasket on it.
Place the new gasket on the pan and then install.
Run the bolts in just until the touch and then go around the pan and snug up the bolts evenly as tighten.
I use a 1/4 or 3/8 ratchet and hold it right on the head of the ratchet so it limits how hard I can tighten.
Once you make your way around about 2-3 times, you are good.
Now it's time to fill and check.
It took ~6qts without draining the torque converter.
Always check with engine running in neutral.
Now one thing I completely spaced out is a drain plug for future maintenance.
Add it to your shopping list and install it during the swap.
They make add on plugs for trans and oil pans.
Another item I noticed is the 618 added a large magnet ring in the pan.
When I bought the pan they showed the magnet but it was not included.
I recommend you run the magnet.