While I wouldn't want to discourage you from picking up a nice mechanical OM body, regarding IR and EOS, I believe a EOS 1V does not use IR for sprocket detection, but something like an Elan 7E does.

And to throw some more controversy out there, since you're looking for a new body...
for IR, I think a range finder or any sort would be preferable over an SLR, just because the IR filters are almost opaque to the human eye. Also, I think the quality of your fine zuiko's might be lost in the IR rendering.

But there's more to taking the photos, than just technical nit picks that I've mentioned.

have fun,