Although I do agree with what everyone else here has said.
um as far as the truck goes, I say you custom paint the old GMC logo in the bowtie and really spin their heads

Seriously though, I don't think enough people know, can Identify or even spend enough time looking to figure it out. so either way I think you are safe. and or the purist...... well I guess it comes down to if you are a purist then it would drive you nuts. if your worried about other purist.... well I almost said something mean.
Hate to be the broken record but it really is your truck roll the sucker how YOU want and tell anybody that challenges you other wise that if they are willing to pay for the changes you would gladly change it out for them

good luck bro.