How to set up TIP to another Sun?

I have 2 Sun Ultra 80’s running and I just got a headless 420R that I need to load Solaris 8 on and set up. I don’t have an ascii terminal so trying the manuals other suggestion of using TIP to connect over the serial. I followed the sparse instructions (A port of the new 420R and B of the running U-80) and entered “tip hardwire” and get the “connected” echoed, but nothing appears when I power up the 420R. I have tried all combinations of A and B ports on both boxes and changing the /etc/remote file. Can anyone suggest something or must I order a Wyse55? The 420R is first of many and we don’t want the cost of a graphics card and monitor.

Thanks,
David