Thinking more about my above post on the rosin, the solder I’m using has rosin core and I’d actually be mixing the fluxes, so maybe the 959T would be best since I already will be adding some rosin from the solder itself:
I have a 21ft. tube of this Ersin Multicore
And a 1 lb. Spool of Kester 44 Rosin Core (will probably last a lifetime)