Mike's Transmissions in Cali is great. Dan is a dealer for ATI and PA
You're not to the level for a really big name converter, but Mike's converter guy reverse engineered a Neal Chance converter and it works outstanding.
I bet you could get itno a really nice and CONSISTANT C-4 for around $2400 that can run all season with just fluid changes. and a damn nice converter for roughly $800.
If you want, I can make some calls Monday and see what I can do.
That 420 is N/A or on the bottle?
If I had dyno sheets and an accurate weight, we can pretty much nail the converter on the first try.