Ah thats the easiest answer. Got it. Thank you!
From my research, with hypothetical numbers, if I have $8000 on Line 11 and every year I get a refund of $3000. It should be as easy as just doing $3000+1875?
If you owe more than $1875 in taxes (what you have paid is immaterial) you get $1875 off your federal taxes.
If your total tax bill after deductions is less than $1875 you will not get the full $1875 only the total amount of Tax you were meant to pay.
It's the total amount of tax you would owe that year that matters.
So if you get the car in 2019 your tax bill needs to be greater than $1875 that year.
Now what confuses people is how people interpret the word OWE.
Many (most?) people will think that OWE means how big a check they still must write in April, & that has nothing to do with whether you get the tax credit or not.
What matters is your tax LIABILITY (aka OWE) for the whole year.
That's the total amount that the federal gov't wants to collect from you (and your payroll withholdings) for the entire year. This liability is the amount that will be offset by the $1875 EV tax credit, and may result in getting you a bigger refund check or at least reducing the size of the check you must write in April.
Hope this help.