L20B Rebuild Information

[Boaty]

What is the maximum overbore recommended for an L20B? I've heard of boring up to .080" before, but I don't think that'd be a wise thing to do, considering the cylinder walls are rather thin as it is. Would a .040" be an OK Overbore, or would that be seriously stressing the cylinder walls???

Also, I'm looking into making my L20B a performance motor. Any recommendations that'll improve performance without seriously denting my pocketbook? Stuff I'm looking into is:

Flat Top Pistons
High Performance Valve Springs
Overbore
Electronic Ignition to replace the old points/condensor dizzy.
Dual Sidedraft carbs, most likely SU's, but possibly Webers (depends on $$$)
K&N Air Filter, w/ a cold air intake routed to one of the headlights.
Port/Polished head
High performance exhaust (Flowmaster???)
Aluminum Radiator (VW Rabbit??)
Flex Fan (A must for those hot stop&go situations!)
Overduration Camshaft (Any recommended brands?)

I consider that a typical high performance rebuild.
Now, some stuff I don't know much about, would be like crankshaft balancing, lightened flywheels, knifed crank..stuff like that, what's the performance gain from something like that? Is it really worth spending the money to have it done? What would a lightened flywheel do for you, except for rev speeds? Wouldn't a heavier flywheel technically be faster for shifting, since the weight/inertia would keep the wheel moving at a better rpm? -shrugs- I dunno.

What do you guys recommend for me to do to my L20B?
What would be the best things to do to it?

And a big question waying in on my mind... should I go all the way and get a turbocharger/supercharger for it?
-would prefer supercharger for it's full power-band effects, instead of a turbo's high-rpm effect.-