@walls6176:
My problem is routing a public IP from firewall1 via firewall2 to the Internet. For example, from firewall1, I am unable to route 8.8.8.8 via firewall2, and on to the Internet via the second ISP.
If the other routes work this will work in the same way. However, I think you'll have an asymmetric routing issue, if you do that.
To resolve, you have to add an outbound NAT rule for that traffic.