Good Luck
It sounds like a nice setup but the problem was the 53 block and the fact you don't know who or how the transmission was built. If it wasn't a 53 block and the transmission build specifications were known the thing would be worth the $10k you are into it. I am into a re-built low mile 47RH and a 12 valve for less than $4000. You can buy a nearly new motor on Ebay 03 or 05 fully dressed for $4500 buy it now priced. With the 53 block that motor is worth no more than $2500, and the transmission is worth $1500. If however you found who built the transmission and what they have into it I suppose it could be worth upwards of $4000. Good luck.
It sounds like a nice setup but the problem was the 53 block and the fact you don't know who or how the transmission was built. If it wasn't a 53 block and the transmission build specifications were known the thing would be worth the $10k you are into it. I am into a re-built low mile 47RH and a 12 valve for less than $4000. You can buy a nearly new motor on Ebay 03 or 05 fully dressed for $4500 buy it now priced. With the 53 block that motor is worth no more than $2500, and the transmission is worth $1500. If however you found who built the transmission and what they have into it I suppose it could be worth upwards of $4000. Good luck.