Driveshaft U joint question.

I am going to be putting an A500 Trans in my car and am going to use the A500 driveline and shorten it.
But for the time being I need to retain the 7.25 rear end until I can get around to swapping it out for an 8.25.
Do I have this right that I need Napa part number 347 or TRW 20226 to go from the bigger driveline and joints to the 7.25 yoke?
This would be 7290 size in the driveline and 7160 size in the yoke on the rear end, correct?

Then when I do swap rear ends I can shorten the driveline again for the 8.25 and go to the full size joint instead of the conversion joint.

Sound reasonable?

Thanks