24 Spline?

Hi, my Series 3 88" is listed as July 1981; 1981 manufacture. Just about to go in for chassis swap and some work on front transmission (fwh) as it won't engage 4wd. Can I assume that it has 24 spline half shafts? If not, is there a visual check to do, short of withdrawing the shaft? Forgive the ignorance, but I am just starting my L-R journey.

It should be 10 splines at the diff. but the drive end you can check by taking off the FWH.

Thanks. I will have a look.

On a nearly forty year old truck you can never be sure by dates or even vin numbers as parts even whole axles can have been swapped in that time. As above take FWH hub off, you need to fined out why it is not working anyway.

Absolutely true of course.