1. Yes,
T-Jacks are the best. Cabinet jacks are crap, don't use them.
2. You can connect a few cabinets together if you've got more than one tall T-Jack, or a helping hand. Sex bolts are an option for euro style, face frames can be connected on things such as maple. You have to pre-drill and countersink.
The secret is putting them on their back and using big wood jorgenson clamps to hold the face frames together when you attach them together. I put one screw through the top on the back so they don't flop around while moving; this I adjust or remove once it's up against the wall, and you can't see it since it's on top above the inside of cabinet.
3. At least the stud finder I use goes right thought cabinets. Transferring lines? For chumps! Studs are preferable. Connecting face frames makes off set stud anchoring fine. Some people connect behind the face frame, but it's weak and causes poor lines.
4. You'd be surprised what screws can hold up a cabinet. Some people countersink and use whatever won't snap off, such at special ordered steel screws, and put in a cap after. Some just use drywall screws countersunk. The big washer head GRK's are great. These days a lot of guys seem set on using impact drivers but I don't think it's necessary. I use a CXS. But I always pre-drill the cabinet to make it easier.
5. However you draw a line, go for it. It helps a lot to get the cabinet in place well. Laser levels are nice, but you got to be really careful because standing next to them can cause the floor to change your line.
