Yeah I had the snowstorm on White Water. I ordered the HV kit from Marco. Luckily I caught a properly labeled package but the part was not the MJE15031 transistor. It was the same one of the other transistors included in the kit. https://www.marcospecialties.com/pinball-parts/WPC-SEMIHV
You'd have to see if this works with Fish Tales. Anyway, after the rebuild the snow is gone. I believe the instructions says it takes about 20 minutes to rebuild. "Installation requires circuit board soldering skills and about 20 minutes." Yes this is true IF you doubled up on amphetamines, coffee and a couple of packs of cigs.
Give it a couple of relaxed 2 hours and you will be fine.