I bought my router mostly for the T-Molding install on my first cabinet, back in 2009. When I built my next cabinet though in 2016 (also a TMNT cabinet coincidentally, though mine is half sized and built from scratch), it was practically my most-used tool.
The most-used bits were the flush trim bits and pattern bits. These have a bearing on the middle or end of them.
I used this to cut out the second side of the cabinet (after the first one was done.) More importantly, I used it to make sides straight (by clamping a known good straight piece of wood to the part I'm working on.) Had to do this since I cut my boards using a handheld circular saw. I don't have a table saw for straight cuts.
(I mentioned there are ones with bearings in the middle and some with them at the end. I recommend getting both, so you can use whichever works best for each operation.)
The "normal" bits also got some use too. By setting the depth, you can trim away some of the wood, without cutting all the way through. Great for making recesses for joysticks from the bottom of the panel. Also, they're great for making cutouts for speakers and such.
I know my examples are more for a scratch build, and you're doing a restore, but that's just some examples. Perhaps you can find other uses around the house? I think it worked great for my cabinet:
(Yes, the cabinet uses a CRT monitor and JAMMA board, not MAME).
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Link to my project build over on BYOAC)