2018 Estimated Tax

I have just completed my 2017 taxes using TurboTax.  Because of some unexpected investment activity that will occur ONLY in 2017, I under withheld my 2017 taxes.  Because of this, TurboTax is significantly over estimating the 2018 1040ES quarterly payments and the four estimated printed tax vouchers for 2018.

I want to "trick" TT to print the 4 forms with a more reasonable estimate.  Any suggestions?  Or can I just use the 4 forms and cross off the printed quarterly estimate and write in my own?