FWIW - called Callaway and asked what product the tour pro's use to fill the sole cavities on their 2-Ball putters. I wanted some extra weight, plus the fill makes it easier to tap down ball marks.
Was told Scotch-Weld DP 420 epoxy
I couldn't find any and used Goop "SuperMend 2 Part Epoxy Paste, Household" with some black paste dispersion mixed in. I would guess that it added about 35 grams.
Used a sharp chisel to "carve off" most of the excess after it cured about two hours. Masked off the painted areas and hand (block) sanded remaining excess, then beveled the remaining "lip" with the chisel.
If I did it again I would run a heat gun over the epoxy right after application. I got some small air bubbles in the epoxy.
Very satisfied with the result. Putting stroke seems smoother, but still need to work on distance control.
/Ed
