In my opinion, it ain't worth it.

Alright, this will hopefully clear up some fog. 

So the spacing system works by a bar in a spring that catches the platen when the return lever is pulled. What controls the spacing is something blocking the bar from moving down. There are three options for this.



You can see the piece in the picture.

The spacing setting is on the side of the carriage right where the screwdriver is:



You pull to increase the spacing  and push to decrease.

Also, for future references, I found where you can change the mainspring tension. It's a knob by the mainspring itself right here:




Hopes this helps and good luck!

P.S. Did you know you can remove the platen unit?

I wouldn't recommend re-painting your Smith Premier. Leave it in original condition, and preserve what is left of the original paint. Unless the machine is covered in active rust, in which case a refinishing may be necessary. These old Smith Premiers actually look really nice when cleaned up and with all of the wear/patina they acquire after over 100 years of existence.

Piggybacking on an old thread:

I've accumulated quite a few early typewriters on the cheap, on account of their condition: Smith Premier, Noiseless, Underwoods, and a few Royals and Remingtons--all in that black paint that seems to be characteristic of most early typewriters. 

While I prefer the "natural," aged look, there are a couple that could use a bit of touch-up paint. Does anyone have suggestions as to what kind of paint, or any other tricks of the trade in dealing with old paint issues?

I used a black, enamel (model) paint on my Remington 10 a few months back--just on the front (steel) plate as opposed to the iron, which I largely left untouched. You could definitely tell the difference, and there does seem to be that pull to paint more and more. 

But just last night, I painted the five tabulator keys on my Remington 12 in the bright red--again with an enamel (model) paint, and it looks just gorgeous. So I guess it just depends on what needs to be painted, and how much--which is something I'll have to consider as I move forward on some of my other salvage projects. 

The antique furniture comparison seems apt, but a bit misleading (as a guy who refinishes old office furniture). If you've got a reasonably nice antique, you probably want to clean it without refinishing it, or altering it in any significant way. But if you're like me, and you're reclaiming old wooden filing cabinets that lived for 80 years in a muffler factory in Dayton, and got painted green and yellow and brown, sometimes stripping the whole thing down and refinishing it from scratch can yield incredible results! 

As far as the comparison goes, a few of my typewriters are pristine antiques that you'd never want to mess with, but most are the $20 pile of metal that was salvaged just before heading to the dump. That appears to be the key difference here.