A few Q's

There's a new donk ready for my esky, another 1600 kent but it's high compression and has a 234 cam. I'm going to bolt it up to the BW35 auto, because thats what I have at the moment with my LC motor, so it will be a simple job. I understand the C3 is a much better transmission but unlike the BW35, it requires water lines and vaccum.
 
Being an auto, will the car struggle under 2000rpm with the 234 cam?
 
This HC motor has its original 32/36 carb and manifold. I'm assuming the guy who dropped in the cam also rejetted the carb. From what I've been told the engine runs great.
 
I have a single 40DCOE32 weber on my LC motor, and thought it would be better on this new HC motor. However it will need to be rejetted. Once rejetted, will the single DCOE be a better carb than 32/36 (keeping in mind that vaccum advance is non existant with the DCOE) 
 
One more... is there any difference between the heads on a LC (1976) and HC (1975) motor? Valve sizes etc? It's just that the head on my LC engine was reconditioned and has unleaded seats. It might be good to make use of it.  
 
Thanks
 
 
 

Timed vacuum advance will make the engine slightly more responsiveness at part throttle and produce better fuel economy on cruise.  This only holds true though if the mech and vac timing curves are spot on (or close enough).
 
Full Mechanical advance is between 32-38 deg on most engines,  the vac advance will add 5 to 10 deg on top of that.  Some factory cars add 20deg on vac because the mech curve is only 5-10 deg.
 
Vac advance can help with a tight stall speed if you cruise a lot below that speed (unlikely). 
You won't kill a BW35 behind a 1.6.  You might smash the clutch pack apply spring (I think thats what you call it) from slamming it from R-D though.