Thanks Terry, this is a big help to this guy. He wants to install the F-head temporarily while he rebuilds the L. Sounds like a simple conversion. He said the engine he's getting has the throttle linkage and fuel line already on it so it should just plop right in! The only other concerns I can think of are the starter circuit could be different if the F-head has a Delco-Remy starter. The Autolite starter spins when you ground the solenoid whereas a Delco starter spins when you apply 6 volts to the solenoid. Easy conversion, I've done it. Also, the Delco voltage reg is different than Autolite but he can swap the Autolite generator and he's good to go. To swap an Autolite starter with Delco and vis-a-versa you need to change the clutch housing. That can be done when the engine's out if that's what he needs to do, otherwise using the Delco and rewiring the starter button circuit is much easier.
Thanks again - I'll let you know how it works for him, he may want to leave it that way.