I’m sure this a question that has answered many times but I am a new member to the club so please bare with me!
I have recently bought a T3 dressed as a Le Mans 2 - (strange I know!) It has got many of the Le Mans parts, carbs etc. the inlet stubs have the 8mm fixing bolts indicating a T3 however it has the le Mans carb stubs which blend nicely into the head inlet.
The casting numbers under the rocker cover are same as my genuine Le Mans - 13 02 21 60, does this mean they are Le Mans heads or simply the same generic casting?
I know I can check by measuring the valve sizes but I don’t really want to take the head off just to check.
Please enlighten me!
Many thanks!
Hugh
Just had a look at the parts books,the LM2 heads part numbers are 14 02 21 51 and 14 02 22 51, the T3 heads are 14 02 21 01 and 14 02 22 01. My T3 heads have LM3 inlet stubs and 36mm pumpers, worked quite well 
Thanks for the info Jez,
Do you happen to know what the LM1 head casting number should be?
- 13 02 21 60?
If LM heads were put on then would also need LM pistons to match, else comp ratio is all wrong. So I’ve been told.
If a photo on Gutsibis website is right, it could indeed be 13.02.21.60, altho to me it looks like 13.02.21.00 (?) But I am having to zoom in a lot to even read it.
I’ve had another look at some more parts books , on motointernational, if you google moto guzzi parts books it’s one of the first sites to be listed. Anyway the plot thickens as they say, Lemans mk1 heads, according to the parts book are numbered 14 02 21 50 and 14 02 22 50,but Eldorado heads are 13 02 21 60 and 13 02 22 60 so I’m a bit confused, it’s possible that Guzzi used up some old stock and modified Eldo heads for the early ones but I doubt it as they have different sized valves and inlet and exhaust hole diameters, most odd 
What we need is another LM1 owner to have a gander at their heads and confirm which number is correct.Hope this is of some help and not muddied the waters too much.
Very late to this thread, so maybe too late.
LM1 heads are
14 02 21 50 RH
14 02 22 50 LH
Hugh it is not unusual at all, in fact it is very common, most engine and frame parts are interchangeable, that’s the beauty of the marque. Mike H had a LM 1 with Spada bodywork on it and because it is more usual for folk to try and Le Mansise a Tourer than the other way around I had assumed that his was so, however he assures me that it is a Le Mans and has the correct frame and engine numbers, stranger things happen at sea!
My 950 was an 850T, has a Convert engine, heads flowed and ported with Le Mans valves and twin sparks and now looks like a 750S, so yours could be a T3 with Eldorado heads that have been re-worked, or any combination of the above and anything else!
Enjoy the bike and tell the rivet counters where to go