stripped threads in trim unit

[DJ II]

The aluminum threads are stripped in the fill hole on the trim unit. If I run a tap in the threads or use a helicoil plug aluminum shavings are probably going to fall into the reservoir. Looking at the part breakdown it shows there are two filters between the reservoir and the assembly. Are these filters going to suffice to keep the metal from damaging the internal components of the assembly? Also would installing the helicoil affect the assemblies ability to self bleed? Motor is 02 F100

Thanks