ford trucks

[1986bronco2]

so as most of you may remember about a week ago i was looking into getting a fullsize bronco with bent pushrods. well they owner never returned my e-mail so i said f*** it and started looking into other potential fullsize trucks and s.u.vs. that said i kept my mind and options and mind open and kept my price range low(under $1000) i had some decent choices and found a 79 f 250 2wd with a np435 4spd tranny and a 300 ci 6 cyl(next to indestructable) as per the research on line. the guy wanted 600 and i got it for 400. can anyone tell me anything at all between the "b" code 300 ci 6 cyl and the "k" code 300 ci 6 cyl? i got on autozones website and was browsing for a few parts and when it asked me for the engine code i looked at the title and saw that it was a "b" code and according to autozone this engine is only found in 7% or so of 79 ford f 250s mine is 2wd also. im just trying to figure out what makes this engine so rare for these trucks. thanks for looking,bill

 

[Mac]

I did a little checking this mornig and didn't find anything about a "K" code. One site listed the "B" as either a LD or HD but kept the same code. Another site that might be better than AutoZone is ; http://www.fordification.net/tech/vin.htm. They only have the "B" code.
I've found a lot of mistakes in the past on parts stores web sites.
Dave

 

[1986bronco2]

i also digging earlier and found the the (b) code 300 6 cyl was found in hd trucks that weighed as much as 5 tons! is there a way i can check to see if this is an hd 300 6cyl or a ld version? such as a block casting code or number? and if so where is it located and how would i be able to tell the difference?

 

[Mac]

Think all the blocks would have the same number. On the FT seriers of truck motors, the HD have a forged crank. All I can think of.
Dave