George,
With later Guzzis identification is easy, and information prolific.
Engine and frame numbers are the key. They won't match as such, but should have the same prefix. A Le Mans MkI is in the range VE 11111 - VE 17311, while a MkII is VE 17312 - VE24086.
MkI Le Mans are sought after, and always have been. As a result, very often later models are "onerised" to make them look like Mk Is. Mechanically, and externally, there is not much obvious difference. You need to be very careful to correctly identify it. Mind you, if it's cheap you can't go too far wrong. All of the "round fin" Guzzis are externally similar, and plenty of touring model SP have been made into MkI look alikes.
Early V twins are long-lived, with 500,000km not uncommon without huge work. Engine rebuilds are usually a matter of new barrels and pistons, an easy job done sitting beside the thing on a box. Original 850cc barrels are not so easily available any more, mainly because the larger bore 1000cc barrels are a direct fit. More torque, re-jetting required, and not as sweet running, but easy and relatively cheap.
cheers, and good luck,
JFerg
