Flip up bumper?

[Earl]

Hi all.

Hope this is the correct section.

I'm currently building a Peterbilt(ish) truck from a KH and want to fit a flip up bumper. I've come across a few builds on here that have done it but non of them go into much detail of how they actually made the bumper flip. So if anyone could point me in the direction of somewhere that shows how to do it I would be very happy

Thanks in advance