Converting a 1300 semi-auto engine to 1600 manual

As you may have read in my previous post, the engine in my 1303 is
suffering from knocking bearings, so is technically dead. As the car
is a daily driver, the quickest, and more importantly - the cheapest -
solution is to get a secondhand engine and swap them over.

The car in question is a 1974/75 1303 (Super Beetle), the original
engine is an AR code 1300 that a PO fitted with a 1641 kit less than
10,000 miles ago. I have personally fitted a 34/PICT-3 carburettor
and suitable manifold.

I have been offered a decent AR code 1300 engine, apparently from a
semi-auto. So I would like to use this in my 1303.

My first question: what is different about the engines fitted to a
semi-auto? I read that the oil pump and flywheel/clutch are different
and would need swapping over from my dead engine. I vaguely recall
that the cam and/or crank is different, but I may be wrong.

The engine was pulled from a semi-auto, but the owner has no idea if
it was original to the car; ie, it may have been a standard engine put
in a semi-auto. Then again, it might not!

If I change this 1300 to a 1641, is it simply a matter of swapping
over the barrels, pistons and cylinder heads to my new engine,
providing of course that they are in good condition? I would like to
fit new piston rings to be on the safe side. I would also swap back
my manifold and 34/PICT-3

Any suggestions? :-D
--
Howard Rose
www.howard81.co.uk
1966 Volkswagen 1300 Deluxe
1975 Volkswagen 1303S
1962 Austin Mini Seven