Been looking into this and talking to a few people and I know it can be done both ways.

On a BW78 Housing would you shorten at A or B.

I am considering shortening at point A as I can put a different flange on the tube as I am not using the brakes that are on the BW 78 Diff.

Have been told that shortening at point B can be difficult as once you drill out the welds and remove the tube from the diff housing, Driving it in again and keeping it all aligned (even on a jig) is difficult.

Any one have any experience to add? I realise both methods will need to be jigged up.

Cheers

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With most axles you can do it either way, as along as the tube doesn't neck down.

Use a jig and final weld it, it wont go out of alignment when you drive it (if the welds are done properly).

i had my done at the A end with no probs yet (skyline r31), cut then sleved

cut the ends off
shorten tube
weld ends back on
all done in a jig
i considered putting 9" ends on my hilux diff using 9" axles and have a massive choice of bolt on brakes
should i again mention talk to phil?:)
dazza

if you shorten it at point A you cant just cut the tube down and weld a different flange on, as the tube has the recess in it for the bearing
you need to cut the end say 73-100mm of the diff off then cut out what you dont need from the tube then weld the end on

when doing it at point B i dont see how it could go out of straight...it takes about 20ton of pressure to get the tube back in again and its in there a good 3 inchs or so...aint nothing going to move it even without welds on it

ive done both ways on BW78s (dad just happened to have a hydraulic ram that fitted inside the axle tube) i did 2 diffs by pressing the tube out and pressing it back in
but just cutting the ends off is quicker and easier to line the end flanges up again

you would be ammazed how much things move around when you use a 20T press on them. even big stuff
if it galls going in it will cock to one side

I will also go with the A end option, agree with your statment.

I havnt shortened a diff before but i know they are easy enough to straighten and bend to where you want later.

The diff housings ive done for racing have to be aligned and camber added and they bend/straighten easily.

You would start with everything as square as possable to start with tho.

I can help you with a diff bender design if you run in to sraightness issues.

Go see Phil
But pick up my housing on the way
I need one done too

add me to that list haha