–Finally gave up on the Leica SL. SL2 focus magnification is so much higher (15x vs. 10x maybe; the web is silent on this) and the viewfinder is so much brighter.
–Tried to paint the Silca pump tube Krylon Sun Yellow. Total disaster. The paint from a foot away hardly showed up on the tube, and from six inches it globbed and ran. I had to go to Home Depot and get some paint stripper. It’s back to normal matte black now. I might try a gloss black Krylon, since I have some, or take it to Powder Coat-It and see what yellows they have.