Im very interested in this but my knowledge of such beast is limited i will be 50 in a couple of gear changes and i promised myself a BSA Mettise .
Kehrist after the hard time you have given me about Harleys and Pommy bikes, you are about to buy a Birmingham gear shredder of your own.
Anyway mate, B44 from what I understand is pre 70 in Aussie and pre 65 elsewhere.
That engine has had all the major B44 issues addressed, Alpha big end, NEB clutch and mainshaft ( splined not keyed) and B50 piston and sleeve in B44 barrel gives good big bore set up. NEB mainshaft is regarded as gearbox fix as stock one flexes and leads to gear failure, NEB one is beefed up and better material.
I think it is a decent buy ..... and if you need to raise a little extra cash Bill you know what I like