torque converter choice

Definetley custom converter, get it right the first time and piece of mind that's it's not an off the shelf item that'll shrapnel when ya stall the bejesus out of it. When it's right she'll act normal (minimum slippage) when you're cruising around not building any heat.

As a side note, if you find the engine's got an off line bog (when you plant the go pedal) loose the vacuum secondary and go with double pumper.