Authorize.net E-checks?

I need to be able to add the ability to do e-checks via Authorize.net. But it appears the only extension that was available for this says it shouldn’t be used because it messed with a core CiviCRM file. So how are people doing this?

Edit: The previous answer is not an option. That page is from 2016 and the information is apparently from back when there was an extension. Without an extension connecting CiviCRM and Authorize.net, the solution there won’t work. It’s just an Authorize.net reseller. They don’t provide extensions and such. So we’re still looking for a solution. Or an estimate as to the cost to get the old extension working so that we can crowd fund it?