Most elements of this have been given by others already; think of this as summing up the current state of the art.
[something] + L + LY; we don't know whether the "2" means "first two letters" or "two different money-related words" or "word denoting two units of some kind of money" or what. We know (because OP has told us) that it isn't MOLLY or DOLLY.
I suspect the car in the first box is a Ford Model T, and this word begins DET. Or it could begin DECAR, but if I understand OP's comment on Rand's answer right then it doesn't. Presumably the D at the end is literal. The middle box is a big mystery.
First box is almost certainly DIS. (I think OP's comment on Steve's answer confirms this.) Second box is a mystery.
So we seem to have
~~~LLY DET~~~D DIS~~~.
Some comments on the start of the first line:
If -LLY is correct, then most likely the first box yields something ending in A. On the face of it, the most likely meaning of that "2" is that we are to take two things-indicating-money; but, while there are e.g. some currencies whose names end in A, none of them seems to give anything useful. (e.g., "...PESETALLY"? Nope.) CENTRALLY is tempting (beginning with CENT) but I don't see any way to justify the RA, nor have I thought of any plausible phrases beginning CENTRALLY DET... .
Some comments on the middle of the second line:
Perhaps the image means that KBK indicates (by being the initials? in some other way?) a name, long word, phrase, etc., that decomposes into a long bit + a short bit + a long bit, and we need the second long bit. [EDITED to add: OP has now posted a hint that confirms my interpretation of the image and indicates that it's a word rather than a phrase.] But so far I've failed to find anything plausible that KBK might mean. And it doesn't seem plausible that what this box yields begins with K ("DETK..."?!!), which you might expect if this is how it works. Most plausible words of the form DET~~~D: detoxed, detuned, detached, detailed, detained, detected, deterred, detested, detoured, dethroned, detonated, detracted, determined, detoxified, deteriorated. None of them very plausible, either in terms of fitting the rebus or in terms of making a familiar-sounding phrase.
Some comments on the end of the third line:
Someone suggested things like DISINTEGRATION for the line as a whole, but I think the "C" in this box has to be significant. If we take it to be a constant then we can get "CT" or "CX" or something, but I don't see that that works. What else is conventionally designated C? Capacitance. (Not a thing that often needs integrating.) Circumference, maybe. (Integral would be the area of some sort of surface made out of circles, like a disc or a sphere. DISA and DISAREA are not words.) All sorts of other even-less-integrable things. It's fairly common to denote the arbitrary constant you get from doing an integral by C, but why you'd be integrating that I'm not sure, and anyway DISCONSTANT is no good and making DISC by starting with DISC, deleting C, and then adding C seems rather unsatisfactory.