We're talking for nothing as we don't know what others chip are... and how they communicate.

If both are 16F88... and the timing is not as this critical, why not using the internal OSC and have 2 spare I/O on each for free.. but we still don't know how timing critical your app is

OK i hear some saying that they used internal OSC and NEVER EVER had any problem even with 115,200 baud ser com...... yeah right