Torque converter id

Yes, you could use the B&M flexplate for the 360 and that would solve the balance problem but not the increased stall speed issue. I would consider purchasing the correct converter for the application and using the one you have for something not requiring a weight but needing the increased stall speed.
So you think the advertised stall speed of 2100-2400 if too much for a van? I was thinking the 1800-2200 would work better since it’s heavy