Restore stock recovery?

I'm trying to restore the stock recovery so that I can take the recent OTA update. All the guides I've found say to download RUU, grab the rom.zip, and extract it. This works okay, up until the extraction. The rom.zip doesn't appear to be a valid zip archive, and forcing an extraction only gets me three dzdata files and boot_signed.img. I've tried with a few different RUUs of the right version, and verified the md5 checksum. (I'm currently on 4.25.651.14.)

So, how can I do this? Or is there a better way to take the OTA?

Some version numbers for reference:

Code:

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(bootloader) version: 0.5
(bootloader) version-bootloader: 3.19.0.0000
(bootloader) version-baseband: 1.09.20.0209
(bootloader) version-cpld: None
(bootloader) version-microp: None
(bootloader) version-main: 4.25.651.14
(bootloader) version-misc: PVT SHIP S-OFF
(bootloader) serialno: HT4CKSF00900
(bootloader) imei: 990004994638470
(bootloader) imei2: Not Support
(bootloader) meid: 99000499463847
(bootloader) product: m8_whl
(bootloader) platform: hTCBmsm8974
(bootloader) modelid: 0P6B70000
(bootloader) cidnum: SPCS_001
(bootloader) battery-status: good
(bootloader) battery-voltage: 0mV
(bootloader) partition-layout: Generic
(bootloader) security: off
(bootloader) build-mode: SHIP
(bootloader) boot-mode: FASTBOOT
(bootloader) commitno-bootloader: 26d3ff23
(bootloader) hbootpreupdate: 11
(bootloader) gencheckpt: 0

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