Cladinshadow

So I have a 95 Legacy wagon 2.2l with a tz102zaaaa 4.11 ratio that doesn't go in reverse. I just moved from a Subaru friendly local in Colorado to Saint Louis MO which doesn't seem to have nearly the love so I had a bit of a time searching around for a used trans that would be compatable, got one from Michigan they assured me was from a 2.2 and when it arrived here it was evident that it was from a 2.5. My trusted mechanic back in Colorado (master tech) tells me I can make it work by just changing out the flex plate with that of a 2.5 as long as the gear ratios are the same but he cannot find any info on the tz102z1aba code from the part I got sent to confirm such for me. Has anyone come across this #? Best I can find is it might have been from a Grandwagon legacy of which I believe was a Japanese model in the early Outback era. Thanks for any help