"shield" is Arduino's terminology for the stackable add-on boards. See...
Thanks for the picture - that clears things up. WizNET's documentation is sometimes lacking. I'll need to make sure they're not doing something equally idiotic on the WizFi810. I have the Wiz110SR so assumed the Wiz107SR would not be a duplicate but w/o a DB9.

It makes no sense to do shields for the Wiz107 & Wiz108 as the shields interface with a µC that expects/uses positive logic. I need to keep the designs as universal as possible. If they have a similar module w/o the transceiver, I'll consider designing the shield to accept one or the other.

And, I do not know when I'll get them built. I have age/health issues (plus hospital/doctor bills) that will delay things. On top of that, nurses from the VA visit almost daily so it's tough to get any continuity going on my projects.

I've not tried the 18F2550 so don't know whether you can invert both TX & RX. Nor do I know whether you can get at the comparators to use them as inverters. Maybe others who use it can comment.