that is correct. a budget boost is pretty straight forward and cheap. after that you get into control arms, brakelines, trackbar etc.
the front can be either a hickey puck style in the bottom of the spring, or a longer poly one to replace your current rubber one.
chances are you'll be fine out back for bumpstops. the big issue is the front where turning while flexing can get things closer than flexing alone.
that particular lift is for an XJ and so that shackle might not be any longer than your current one. MJ shackles are longer than XJ. you'll want to call and see what they measure.
be aware that a change in ride height can expose how bad any worn out parts are. and might need an alignment. it can still get expensive to do, but usually it's now a matter of replacing parts that are bad rather than simply too short.
and lastly, that is an INSANE amount of money for a budget boost. you should be looking for front spacers for under 100 USD.