Default [Q] Re-install stock recovery WFS-VM-USA

Hi ho, all. Maybe one/some of you can shed some light on this...
I have a WildfireS (CDMA, Virgin Mobile in the US, S-OFF RL hboot-1.06.0000 microp-0354 Radio-
It was rooted with installed CWM recovery, but I had to reinstall the stock ROM from RUU.
I want to install the stock recovery, since I think the CWM recovery is prohibiting an OTA update that I need to get back root.

Question is this:
If I put the correct version of the stock recovery on an SD card as, the recovery should find it, recognize it and replace the currently installed CWM, right? This has not worked for me in the past and I'm wondering if it's an issue with the versioning of the .zip, or if flashing using this approach is somehow flawed. The RUU that I used worked, so I should be able to flash the recovery from the same RUU, right?

Tangentally, is there a reason that Shipped-roms doesn't list USA roms for WFS, i.e. Marvel? Lawyers?

Thanks in advance,