RPF PREMIUM MEMBER
With the clamp, you either have to allow for the inner tabs or you have to remove them so the clamp will sit flush when wrapped around a 1.5" diameter tube.
I'll be honest, the beige grenade looks the best, but the neck was cast with the windvane unscrewed, and it's missing some material. If you're able to drill straight through (small drill press or lathe) I would use the white neck, beige grenade and putty in the seam-line to smooth it out.
If not, go with the white one, best all around. You're right about chopping the booster, most saw blades take away like 1/16 or 1/8 or material. Now that I'm looking at all this, I remember I did projects like these but was stopped, because I really needed access to a drill press to run straight through everything. A dowel and some glue could hold everything together.
I've gotten some good flush cuts in resin with hacksaws, I rotate them after sinking 1/4 of the way in, rotate, cut, rotate, cut, etc. spiraling around and it usually yields better cuts than running straight through
There are little miter boxes for small parts, but I'm more of a "lets see if I can swing it" kind of person