tale of 2 tops

[60_project]

I know this has been rehashed a few times here, I read the old threads but had what appear to be new questions...

I purchased my 1970 2wd blazer with no top. I then found a single wall in decent shape so I bought it. This weekend I found a double wall in decent shape so I bought that one too. Here is the dilemma, which to use? both need a little repair, and both have some sagging, more on that later.

So the truck is set up for double wall only, it does not have captured nuts for single wall. The double wall looks much nicer on the inside and the truck will have the top on 95% of the time. Single wall obviously is easier to unbolt. They seem to weigh roughly the same my buddy and I picked up each and put it on and off the truck so each can be handled with 2 guys (in fairness I am the small one at 225lbs)

so any other benefits to the double wall, is it quieter on the road? any other disadvantages past needing to remove side panels to pull the top?

Now to fixing the "sag" this is a 2wd and will be low enough to see the top and it is going to be gloss black. How has anyone smoothed the top? I am thinking this is advantage double wall also, Rage Xtreme is safe for SMC can't I just lay a coat of filler and block it out smooth? with a double wall the interior panel hides any sag.

I am leaning to using the double wall but looking for any feedback.