how can i remotely control a macintosh centris 650

I have an old Centris 650 with some NuBus cards that I still want to use. I'd like to remotely control the Centris, and I would think there are two possible ways to do it: remote control via Ethernet, or emulating the mouse and keyboard (and sharing a monitor). So far, neither approach seems viable. I can find ADB->USB adapters, but not the other way around. The Centris is currently running OS 7.1, though I have installers up to 7.5.5, if installing that would help.

All I need to be able to do is boot one or two applications and make simple adjustments to their UIs.

Anyone have any suggestions?

thanks!