I figured out how to remove the board, pulled the SIMMs, gave it a bath. Re-capping this thing was no joke! I have done a fair amount of customization of computers and audio gear, so have done quite a bit of desoldering. I guessed that because they were surface mount, that they would heat and come off easily... They were more difficult to remove than most through-hole parts! The solder pads on the caps are huge and absorb a lot of heat. My iron was as hot as I dared set it at, little chisel tip squarely on the visible portion of the pads. Problem is that half of the pad is under the cap, which makes a challenge to heat sufficiently - especially without lifting traces off of the board. I went over the pads with flux and desoldering braid, heated through and tried to nudge slightly. Only two out of six came off without problems. The other four each lost a solder pad from the board. I took my time, but the results were still sloppy. I replaced caps C3-C7 and C13, then gave up. If it works better I will leave as is.

I had a 1uF cap on hand, and a surprise pile of 47uF which I haven't needed, I used radial electrolytics. Replaced the original 1988 battery with a new one. Gave the ROM and RAM sockets a bit of a scrape. Reseated socketed DIPs. Brushed some of the fuzzier components with isopropyl. Now I am waiting a few hours to make sure it is dry before I try booting it again.