Diff leaking around the bolts

[Synchro909]

We've just returned from our National Model A rally. Over 1500 miles and the car didn't miss a beat. Averaging about 80 kph (50 mph) on the open road, it returned 23 mpg (that's about 18.5 to the US gallon, I think) Not disappointed about that but now that I'm home, I have a job to do on it.
I'm guessing that the guy who restored the P/U in Manitoba (Canada) didn't know what he was doing when he chased the threads in the diff centre and that left them too loose to seal. Oil leaks around the larger end of the axle housings - so much so that I had to top it up twice during this trip. If there is an easy and a hard way to do a job, I prefer the easy one so this is what I propose doing. I'd like feedback if my plans are unworkable so as to save me turning an easy way into something else.
I devised this while driving and I think I have a way of doing this repair without the diff centre coming out of its bearings wich would make reassembly a PITA.

1. Drian the Diff.
2. Jack up the rear of the car and put jack stands under the chassis
3. Dissconnect the brake rods
4. Using a spring spreader, undo the shackles and leave the spring in the U bolts
5. Lower axle assembly and put blocks under the centre and one end
6. Remove the hub from the other end, undo the bolts around the axle housing and slide the axle housing outwards about an inch
7. Clean/repair and seal at the gaskets and around the threads. I thought I'd use Permatex #3 for that.
8. Refit axle housing and hub
9. Repeat on the other side.
10. Reassemble (including put oil back in it!!)

By doing one side at a time and leaving the hub on the other side, I think the diff centre and axles will stay put while the housing is moved out. I will only need enough room to get a finger in there with a rag over it soaked in petrol to clean it before sealing it so 1" should be plenty.