Sky Rider is getting LEDs under the playfield and behind the backglass. Leaving the visible lamps incandescent.
Sky Rider got a chime unit transplant (out with the Williams chimes, in with a Chicago Coin set of chimes via eBay). I've also got a parts on order to replace the chime bar grommets / washers as well as the bumpers under the plungers.
Duotron got a flipper coil upgrade (Orange Dot) after a brief sojourn into the land of the yellow dot (too strong for the game)
Duotron has, and Domino is scheduled, for 3" levelers in the back so I can play with the slope a bit; previously maxed out the 2" levelers. I'll probably spend some time leveling everything out somewhere along the way.
Also got in some adhesive back foam insulation (marine grade 1/2" stuff) that I'm gonna affix to the back doors of all machines - Sky Rider came with something (which is a bit yellow'd and probably full of nicotine) but it really does quiet the game down a bit and make the doors feel more solid, so I'm gonna take care of all three.
I've got a bunch of little projects with all three - Duotron has a score reel that is a little sticky (although it's been behaving lately), and I'd like to figure out the Domino coin and credit circuits (not sure if they work, not sure how they are set for free play, credit reel seems gummed up) as well as Sky Rider (set for free play, not 100% sure how, and the hi score award is set to add a ball which annoys me a little (I want to hear to knock!)
And meanwhile, it's not really all that much of a break for me - yoga studio is closed (I don't have to teach my usual 4x a week) but we're live streaming yoga classes 1-2 times per day (I'm the techie - lights, audio, streaming device) and my engineering work seems to be booming.