You can put heatshrink on the wires if there is no hole where the wires came out.
When I replaced the whole FFM, I put a wire loom on all the wires.
It looks more exposed than what I want to so hopefully the looms help with reducing the chance of melting wires.
I also put a dab of RTV where the wires come out just for prevention and protect that holes.
1995 GMC Suburban:
PMD in Bumper
Leroy Diesel Flight System PMD
Leroy Diesel Oil Cooler Line
4" Warpspeed Exhaust
Kennedy Diesel LP/OPS Harness
Bosch Duraterm GP