Yup, remove the computer.
For simplicity's sake, you could find a distributor for a 305 without a computer from the same application. Look for an older 305 truck and that way it will already be tuned close enough to get you started, and maybe close enough to run that way forever. It won't be performance tuned, but it will work.
Or, you could get any chevy big or small block HEI with a vacuum canister from 1975-later and retune it for your application. The other option is to get an aftermarket HEI. They're not very expensive and come with all the parts to tune it. Summit has one for cheap.