Have installed Salisburys in SWB series in the past. Its vital that do you DO NOT point the nose of the diff upwards, Keep it horizontal.

2 reasons 1 the pinion bearing will not get proper lubrication , and more importantly you will get vibration, you will need Double Cardan joints to eliminate vibes & the shaft is too short to do so.

Move the diff rearward on the axle by drilling the centre bolt holes as far forward in the spring perch as possible .

I would however not install a Salisbury on a SWB now that there are better options.