Well so far as usual nobody around here has heard of any of the two engines were taking about Hotrods 4BT or the 4-53T.

I will come across the 4-53 or 4-53T sooner or later on a farm somewhere but no farmer in his right mind would ever part with one of those untill they retire and then the Auction people come.
In the meantime if anyone can post a pic of a 4-53T out of a GMC truck that would be nice.?

As for the UPS version 4BT I do not know were to look for that one,? Did they use them in other GM vehicles like grumman or bread trucks or only in UPS trucks.?

Is Deisel Powers post true that a 4BT cummins gets 30MPG in a truck or van I don't believe it maybe more like 25MPG if that, a gasoline 292 engine can do close to that if geared right too.

As for price judging by what I have seen so far a good running stationary diesel inline engine gets around $1000.00 at farm Auctions that runs good.
A rebuildable core maybe should be $100 t0 $300 depending on the case.