I took the engine out of an 81 California Westy.  Put on new heads,
new cylinders/pistons, new seals, changed fuel line rubber, cleaned
and painted the tin then reinstalled everything.

I hooked up everything but the darn engine won't idle.  It will start
and if I hold open the throttle it will stay running (although it
sounds a little rough to me)

I set the timing as per Bentley (5 degrees after) and even changed
the fuel pump and filter with a known working one. (at first I
thought it wasn't getting enough gas)

Still no idle.  Has anyone had similar trouble?  What have I overlooked?