It is generally not a simple matter to move a loader or backhoe to a dissimilar tractor. The subframe that supports the attachment is generally a custom job for each tractor model. I am familiar with CK and DK models but not LBs.
Black smoke indicates Diesel fuel that is only partially burned. The most likely cause is old fuel and/or poor injector spray pattern. If you want to address it, I'd start with fresh fuel and a new fuel filter. If it still smokes, take the injectors to a local Diesel shop and have them tested and rebuilt, if necessary. The injection pump is probably not the problem, which is good because they aren't cheap. Failure to charge is probably the alternator or a wiring problem, either should be easy and inexpensive to fix. Unless you know they were recently changed, I would also replace all filters and fluids. The "engine rebuilt" comment is cause for concern; what, exactly, did they rebuild?. How many hours are on this thing? These engines should last for thousands of hours unless abused (overheated, oil not changed, filters missing or not changed, etc) or something broke.
Many of my neighbors have multiple tractors so they don't need to change attachments all the time. They just crank up the machine that already has the required attachment.