Always go with the electric choke - pros are: easy to hook up, makes the manifold look less cluttered, removes potential coolant leaks, easy to adjust, easy to replace and are readily available. Cons are: need to delete coolant connections so it requires either plugs or the coolant barbs replaced with a single straight barb for the heater hose, coolant port should be sealed as a safeguard (under the base of the carby) Using the 38/38 will ensure a full power curve and has some breathing space for a bigger cam and valves, bigger ports and a more aggressive tune (a 2.6 with serious head work won't run out of breath @ 8,000 rpm)