Obtained some rubber grommets to fit the precut holes in the rear fence baffle.
Slipped grommets over plug wires, routed CHT probes thru the grommets as well, then installed plug boots onto the plug wires. Installed onto plugs.
Still have to order crankcase vent tube (5052 alloy, .035 wall thickness, 5/8" OD) and find a grommet that will fit it. This will route thru the rear baffle thru the left-most hole in the first picture below.
3 holes in rear baffle (left will be for case breather