It's your call whether you should ream your 16-4 to 327... it
will have a negative effect on the value if you choose to sell it, but it will also have a positive effect on the usefulness of the gun
if you want to shoot the most powerful of the 32 family of straight side cartridges. It has to be your call.
I had a Model 66 ND converted to 327 FM (see
Project 616) and ended up with a stainless version of the very gun you propose. I can say without fear of contradiction, it
is loud! I consider it interesting to shoot, but too noisy (with full house loads) to be considered pleasant and fun. This is a serious round coming out of a serious gun.
If it were my gun, I would probably spend some time researching the most effective 32 H&R loadings available and try them before making any modifications to what we know is a rather uncommon and valuable model. Then if you really want to keep the gun for a long time and want to get the most performance out of it, I would then, and only then, consider having it recahambered to 327 FM. Then again, it's your gun, so do what you think is right for you.
Froggie