This information is for the 1932 B-410 Sedan Delivery but I think it still gives some insight into the profit potential for a Briggs/LeBaron converted Tudor. The suggested retail for a B-55 Tudor was $450 and the B-410 Sedan Delivery was priced at $520.
In the first letter, dated Aug.30, 1932 it states that the conversion at LB cost $90 for a Tudor shipped to LB at dealer expense and the second letter, Sept. 26th, quotes the $520 price, arrived at for a SD shipped direct from Detroit.
While not a direct comparison to the pricing of the Model A delivery I thought it interesting that one could have the conversion done for $90.