Im getting an order together from mcmaster carr for an LT build. Im looking at part number 6494k32 or 5967k82. If I welded a flat plate to the end of my tube would this work for an upper bearing? It has a set screw to secure the shaft as well, would that take care of thrust?

Ive done enough reading to gather that an upper bushing using the mad motor plans wont cut it using the larger HP engines. My other option is to order the whole upper bearing assembly from beavertail, its just a lot more expensive.

I wouldn't trust the set screw to hold the shaft in place. In the long run I think that you'll find those pillow block bearings don't hold up that well, I've run both the pillow bearing and the Beavertail housing and no question the Beavertail runs smoother, plus it has a seal built into the top. The pillow block will work but if it was me I'd spend the extra money for the Beavertail setup, just my .02.

I have ran that for years now without any probably, just drill a same dipole in the shaft for the set screw and use some lock tite on the set screw