I use the gutted out thermostat approach.

I've never ran one in my racingjunk, it never gets over 200 even on the hottest days/nights.

I use a 160 thermostat with 4 3/16 to 1/4 holes driled in the part that does'nt move.This lets hot water move past the stat to keep it from cycling and the stat lets the motor warm faster on cold mornings.with the holes in ther you can also plug the thermostat bypass and stop hot water from going back into the block.Bill.

i do the same as TODD74, just gut the thermo and keep the housing in place. it will restrict the flow.