Single or Twin turbo setup for 360?

A single turbo is all that would be needed for towing purposes.
You would not need a big turbo to do this. It would be helpful not to use a large one or one someone would use in a racing car. The goal would be to create boost early.

As mentioned earlier, a 408 would be a great place to start but that is just the internet spending your money. A great idea. But throwing money at an issue, real or not, like the USA government does at its issues is t something we all have in the bank.

Stroker = $$$$$
Turbo = $$$$$
Fuel system upgrade = $$$$$
Ignition upgrade = $$$$$

The idea of a Torque Storm centrifugal charger is IMO, not the answer since that is a rising boost curve rather than a properly built turbo system of almost RIGHT NOW - BOOOOOOST!

A roots super charger is boost now (AKA - Torque and lots of it.) starting as soon as the go pedal is pushed.

Pistons need not be forged and can be Hyperutecic but ether way, ignition timing is critical.

Good luck on your endeavor.