you may need a 96 5.2 flex plate and 96 5.2 TC in the 89 trans

the 89 is pre-magnum and 96 is magnum both N balance but may have slight difference in balance between Pre-mag LA and magnum engines.

but the bellhousing bolts right up from V6 to small block LA/magnum v-8

I have a 88 v-6 flywheel on my 91 5.2 NV4500 both were pre-mag engines though.

you may need the 5.2 flexplate/TC if you need a crank sensor?