The pinion bearing is a light press fit....but does not need a press. Just put the flange on and smack it down far enough to get the pinion nut on....then use the nut to push the bearing on the rest of the way.
Getting it off is another issue usually. Beating on the end of the pinion could damage the threads or could leave dents in the outer pinion race. I usually use a press for that.
The yukon gears are good qual.....probably has the usual "304" on the ring......maybe T8 529 304 67.

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01 Taco xtracab V6 auto TRD white
mostly stock
88 Runner/V6/auto/31"/5.29gear