This may be controversial and circumstances are different for each of us...and perhaps depends a lot on the year's and models.
To "modify" will usually require not one...but several modifications as you do one, it will require another and another and another, and is generally very costly.
That being said, I "dare say" that many many times we can "restore to original" with less money than all the modifies and have a true classy/classic truck.
If I ever find one that is complete I would definitely "save it". However, most of mine is in pieces and already "modded" in many ways so I drag them home and use what I have and access to.
All I can say is basically "to each his own" but PLEASE, don't ruin a great example of Americana.
Thanks for listening.