Proper junk yard etiquette?

[gotta240]

Today i was in a little predicament and was wondering what the proper junk-yard etiquette is for such a situation.

Found the best car i have EVER seen in a junkyard. RHD silvia, COMPLETE minus motor. EVERYTHING there. My friend called me to let me know and i raced down there as quickly as possible. When i got there there were two guys who had already been working on the car for 4 hours. They had the whole interior out, side skirts, wheels, etc.

They said they were going to cut the whole front of the car off and take EVERYTHING except the rear half.

The question is... Is it ok to say, FUCK YOU, i'm taking the trunk lid and rear valences since you guys dont have them off yet and you're working on another part of the car, or is it proper to let them have first dibs at everything since they got to the car a whole 4 hours before me and were actively working on it?

I'm not looking for badass, thug, mr. tough guy answers. I'm looking for the PROPER thing to do. You know, where you can still sleep good at night.

Thanks