8.25 gears in a 8.75

dusterbnb said
Does the 8.25 have 5x4.5 lug pattern?

It depends! 8.25" rear ends were used in Dakotas and other trucks which would have a different number of lugs and/or pattern.

There may be some other slight differences that may affect some parts interchangability between 8.25 rears, but I don't have the details.