64 pitch gears for TC3 to minimize damage?

[OldSchoolGuy]

I just finished a total overhaul on my TC3 touring car, including a brand new Kimbrough 72 tooth, 48 pitch spur gear to replace my damaged original. After only one run in a less than ideal parking lot, I sucked up some grit and mangled my brand new gear on the first run! Grrrr.....

So I was thinking, would 64 pitch gears with their finer teeth possibly be a little more resistant to getting larger grit stuck in the teeth destroying them? Right now I'm running the stock 72 tooth spur and a 26 tooth steel pinion for an overall ratio of 6.92, which is right in the range recommended by Novak for my Super Sport SS5800 brushless motor and ESC. I can switch to 64 pitch 100/36 combo and the gear ratio would be almost exactly the same as with the 72/26. Has anyone switched to 64pitch gears on their TC3/4 with good success? Pros and cons?

And finally, checking the Kimbrough website, I see they are now making only carbon pinion gears. Has anyone tried these? They come with a metal ring to clamp them to the motor shaft. How is durability, wear, noise, toughness, etc?

And while we are on the subject of less than ideal parking lots, today was the first time ever I got some pebbles stuck in the steering gear and jammed it! Never had that happen before. I can see now why Associated ditched that setup and went to the NTC3/TC4 style steering. Any tips on preventing this from happening again other than finding a cleaner parking lot?
Thanks everyone!

[GoMachV]

AE actually had a sheet showing how to make dust covers for the steering ....

https://img2.associatedelectrics.com/pdf/cars_and_trucks/TC3/tc3_rack_cover.PDF

[Frankentruck]

It's been a long time since I've run 64p gears. I recall the mesh being hard to set. Too tight, spur gear gets chewed up and stripped. Too loose, tips of teeth on spur gear get taken off and gear gets stripped. If you think you need more durable than 48p, then 32p is the final option.

[OldSchoolGuy]

Thanks for the replies guys. Yes, now I do recall seeing a document form Associated about the steering gear cover, will have to look that up again.

As for the gears, durability or strength is not what I'm after here. I thought the fine pitch of the 64 would be less likely to get small sand and grit stuck in the teeth like 48 pitch or even worse, 32 pitch. I'm thinking the smallest debris that would be able to get into the fine pitch of a 64 would tend to be softer or less damaging than larger debris. I don't know. I suppose I can always try it and see what happens! No matter which way I go, I better stock up on extra gears. But for sure, I will be looking for a cleaner running area!

Has anyone tried closing up the gear clearance hole in the chassis? Or would that be possibly worse in that if it was closed up, there would be no way to evacuate debris coming in from the top, thus making the problem of gear contamination even worse?