Hi Brian,
I did basically the same conversion to my '47. I purchased these
spring perches from Classic Parts. I've attached a photo (not my photo) of what my set-up looks like to include the plate to maintain the original rake. Be sure to get the pinion angle set-up before you weld the new perches in place. The axle on my truck is in the stock location. Some center the axle in the wheel well, but you may need longer parking brake cables if you go that route.
Let me know if you have any other questions.
