API Gateway -> Fargate using VPC Link, CloudMap, Service Connect and no Load Balancer

I have a simple web api that's running in Fargate with an ALB and working great but the cost of the load balancer is not worth it for this project. I've started to setup using a VPC link and CloudMap with Api Gateway instead but can't find any complete tutorials on how to accomplish this and getting "Internal Server Error" hitting my Api Gateway url with no sign of anything in any of the logs.

I believe this is because I don't have any CloudMap Services Instances. When I try to create one it asks me for IPv4 and IPv6 address and a port, which I don't know where to get this from.

My current setup:

Api Gateway

• Http api
• $default route
• CloudMap Integration for $default pointing to my VPC Link

VPC Link

• VPC link for HTTP APIs
• 5 of 6 subnets (one could not be added)
• Security group to allow inbound http access to my api's port 80

Fargate

• Service uses Service Connect, Client side only

CloudMap

• Route 53 Health Checks

Thanks, Jon