What's the back profile, that's monstrous sidewall, it's like my 4x4 !!

You should watch Fireball Tool he built a monster vice that crushed normal vices ..

back to the diff.
The pinion shaft was refitted with new bearings and crush tube.
There seems to be differing opinions as to what  the preload should be set to.
 
With the help of a new vice, I got the diff flange held firmly, and cranked away on the pinion flange nut.
The force required to begin collapsing the crush tube soon became more than my longest Sidchrome socket bar could handle, and also the  torque wrench (not that I should have probably been using that anyhow for this). But a longer length of bar got things going, and the slackness was soon taken up. After a few goes, there was friction on the flange staring to happen, from 'freely turning' to 'slightly loaded'. All good so far, and happy days.
 
My manual shows a Ford device of lever with weight that adds calculations for expansion and how full the moon is, so I used the fish/luggage scale to measure the pull needed. Here's where the different suggested amounts of pull come in. At 1" from the pinion centreline, preload is meant to be 20-26lb, to start the pinion to turn.
Using the flange bolt holes at 1.75" or so offsett, makes it 12-16 pounds.
 

After a few goes, I got readings of highs 10's, to around 11.8 or so (ignore the scale pic, was hard to photo and pull at the same time).

That was with bearings lubed with new fluid, and pinion seal fitted.
So there's no play or end float in the pinion bearings now, and technically for new bearings I believe the values are meant to be even higher, again. It just seemed to be getting too much, and I wasnt game to go even higher. Some guys i've read suggest the force needed to turn the flange is about a 'firm handshake', and another that you should be able to use a thumb and 2 fingers on the pinion nut to turn it, which is at the very low end. Currently I have left it at 'a pretty firm turn' on the flange to get it to turn, certainly you need to hold the housing with the other hand or it all turns as one.
I hope its not too tight, otherwise its 3 steps back and replace the crush tube again....
Assuming its ok, the carrier is on, and cap bolts are now tightened. I have a dial gauge to do the backlash next, and to get the carrier spaced correctly.
Any thoughts/criticisms greatly accepted.
 

Don't forget to stake the nut once you've got it hunky dory or it'll all come loose real fast.
Still want to see a limslip diff in the before you close up the diff tho. 👌
The diff in my ute has so much backlash it smacks between gears . The slop is about 20mm back n forth on the pinion flange, still quiet while cruising.. It should be about 0.005th . I reckon the teeth will be shaved to a point lol

Question: If you work in a 'car shop' in this case Repco, should you know what Prussian Blue or Engineering's Blue is?
No maybe not anymore. I guess people dont do their own diffs anymore. They were helpful, and suggested Aliexpress. Hmm.
Anyhow, reassembly is a slow process, but getting there. Pinion preload has been done, now working on the backlash between the crownwheel gear and pinion gear.Dad had a dial guage indicator as you do. The manual says to do both side wheel adusters up tight basically, with 0.001 to 0.002mm of backlash, none in effect, then slacken  off the diff side one to give you the correct tolerance. Spin the crownwheel around a few times, and measure the slop with the dial guage. Thats going from memory, so dont quote me exactly. Then you can play with the Blue, to see how the teeth are meshing.Test setup on the bench

I found a 3d stl file of the proposed Negair motor, so I've started printing a full sized mockup to play with.

I needed to slice it into about 27 bits that the printer could handle in size.
Thats 5 pieces printed so far.
 
 

I'm wondering if anyone has had experience in making a gearbox adaptor plate?
Sourcing some 1/2"- 5/8" 6061 Aluminium plate seems to be a challenge, especially when you only need an 'offcut' of around 600m square.
Its to adapt the four speed bellhousing shape to the electric motor profile.
I could just use ply for now as a mockup, or buy ready made (around $1900), but we are still playing around at this stage.

hi Marty, thanks for the link, there were a few good tips.
It basically confirms how I would have done it pretty much. 
Why Ally? because if the bling factor of course!
 
No, I do actually need to be careful of weight, and I can work with the aluminium easier, once I can get some.
The only thing i'm not too excited about, the use of steel thread inserts. I had pictured though bolting and using nuts where possible.Hopefully some progress tonight and over the weekend.
 
 
 
 

just checking to see if anyone has a one piece tailshaft they'd be happy selling?
I have the gearbox but did not get a tailshaft with the car. Ideally closer to Geelong would be good, to save the posties back  :)
Yesterford supplied some new spring bushes, then I can refit the gearbox and dummy fit an adaptor.
Marty I think the anti tramp rods would be a good idea, and might fit them next strip down.

I'm not looking forwards to what is going to happen to to the costs of steel and aluminium in the near future!

I'm not looking forward to the price of anything in the future, fuel, power, gas, rates.... Food even ...

Mark, most car belhousings are ally and are usually 10-15mm at the thread end. There's always helicoil to help, but if possible I would Tig a small ally block behind the hole so the threads go deeper and have more bite... If space allows..