The thing with the gearing is that an automatic LTD with a six needs more gears than a V8...it's doing more work, after all! I give you two options (just like the gangster in Home Alone!). Take the easy road and get a Castlemain Rod Shop 5-speed Toyota gear box conversion, or optionally the T5 manual from an S-pack XF sedam/wagon/ute. BW diffs are on most big Oz tanks. As long as its 25 spline axle with a crushable spacer, you can shove in the lower 3.23:1 gears or even Valiant/XA 3.5:1 ute gears or 3.45:1 pre EL gears, and do the clutch master change and peddle changes. The electronics for each model car were dedicated, so you may have to change them, but you should be able to wing it with no changes. I don't know, I don't do electronics. You'd need to get the RTA to check it or get an engineers advice, but that would be the easy route to getting some life into the old girl!
But there is another option, if youre a glutton for punishment:-
(Don't read this unless you are into keeping the car an automatic)
What I've been doing with my 84 XE is fitting a non-electronic American AOD 4-stage trans to it. If you have a local Ford V8 engine importer, grab a 302 EFI trans off on non-4WD truck or sedan/Mustang. Can't be electronic! The Americans think that it has a nasty throttle valve, but it is not as bad as the old Borg Warner 40 kickdown. It is fairly heavy (38 kgs more than the BW 40) but it is strong on a six, and only needs an adaptor to fit it. You use a 351 flexplate with no balance weights, and a 351 LTD spec drive shaft and starter. The V8 guys are starting to use them on their 351 Cleveland XY to XE cars which came with FMX's, and they are easy to fit on them. It is a modern day FMX trans with no electronics but it does have a lock up clutch. The Mustang torque converter is quite loose, and with a set of 3.45 or 3.23:1 gears, it would go well. It's just a strong as a BTR LE auto (EAII to date) but with no elctronics to get in the way. Often, the Aussie importers hear about its bad reputation being V8's and can't get rid of then cheap enough. As long as your not hammering them in top gear, they are a good trans.
Here's what I did:-
1.Do a Google search on the internet, get all the info on AOD transmissions,
2. and then grab an old FMX trans with 351 flexplate and the metal sandwitch plate, some alloy tooling plate 10 mm thick and 470 mm square, and a trashed auto 4.1 block, with the crank still in place.
3. Make a template of the FMX bell housing, which is the same as the AOD, and transfer the bw 40 bellhousing pattern on it.
4. Then get a machine shop to trace the patern out in 9.5 mm steel plate. Then place a steel 9.5 mm plate on the crank the pace out the flexplate to where it should be, and use the 4.1 BW 40 sandwitch plate and 351C /FMX sandwitch palte on each end.
