I've had many friends and family out in my shop, not once has anyone asked me if the guts were still in my pumps.

I've bought and sold many pumps, not once has there ever been a discussion if the guts were still in them.

Bottom line, it really doesn't matter either way.

If it makes you feel more like a purist then leave them in as you slap on reproduction glass, reproduction replacement parts, and shiny non original paint.