bumper modification

[Kidpaint]

I feel like this is a no brainer and Im overthinking it. I am back to work on my 67 chevelle. The look I started and am still going for is a skinny bumper in the front and rear similar to the 67-69 camaro. What Im thinking is taking 2 of the front bumpers and cutting the upper portion off both.



Problem is on this section that the top is rounded front to back and the bottom part of the cut out section is flat. So I want to split this again length ways from left to right down the middle, again for both bumpers. Then I would flip them over and weld together down the middle of the seam.

Similar to a bumper like this sketch I found online



Whats the best way to cut these down the middle and still have a good seam when put together. So the 2 halves match so to speak.

Heres is the top portion of one cut off. Its hard to tell but the left side is flatter than the right. I want to cut that off



So basically it would look like this but rounded top and bottom