Since you live in a rural area, buy some PVC pipe 75*-100mm diameter *preferred, cut into lengths about 500 mm long and then buy some Talon wax blocks from an Ag supplies shop or anywhere you can buy pest control products. If you really want to be professional, buy some junction caps (not sure what the correct name is) with the removable caps and make that the centre where the bait goes, and have the pipe either side. You're effectively building what most companies use for Rodent bait stations - those black plastic boxes you sometimes see.

Place them around the cars or area where the cars are stored and then monitor for when the blocks need replacing. You just need to be careful that no cats or other natives can get into the pipes to get to the bait, that's why you only use 75mm ideally. Also suggest cleaning up any carcases fairly promptly so cats don't ingest the bait by default. Otherwise tarp and sandbag like they do the grain bunkers but you would be surprised at how small a gap a mouse can fit through.

If you want to attract them somewhere other than the cars for trapping rather than baiting, try Peanut Butter as a lure or grain rather than cheese. It is a bit of a fallicy that mice like cheese as much as they do.

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just get some snake poo

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65 panel van Sprog
73 panel van Iggy

What are the rubber boots like around the magic wands?

Could they be crawling along the gear stick and wriggling through the hole in the carpet?

I have an engine conversion so not 100% sure if it applies, but I have one 1" hole in the firewall that leads down into the space behind the pedals, where the pedal bolts to the back of the firewall. It's the space you have to reach three hands into from under the dash, to get the pins & clips in the bottom of the clutch & brake cylinder arms. If you've done it once you'll know it well, & have the skinned knuckles to prove it! As I said, not sure it applies to you.
Otherwise, mice can get through any space they can get their head into, so around 10-12mm will be enough.
Assuming they can't get to the two holes at the bottom of the battery box or behind the rear number-plate, check & re-check the firewall. Put grommets in everything & find out which ones have been chewed. Once they find food, they'll want to come back in.

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1.8L Sunshine - Legal, legit & lovinit

Snake POO?????

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1310/71

Thank you for you reply,,,,Maybe we will just make a cat door into the shed, so our cats can get access, and do the job they are meant to do (Not lay around all day sleeping )

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No access at those points

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Thanks for your idea's, Some Car's may have access though the holes in the battery box, so will look into that.

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