I'm looking to find 4 of the aircraft engines for a 1:64 b-17 to use on a trailer load and haven't had any luck locating them, the engines that come with the kit that I will be using for the rest of the load(s) is the Lindburg kit and the engines are cast as one with the cowls, any help would be appreciated. Also if you are curious about what the loads will be I intend on doing a thread with the load and truck progress as I get going on the project. The intent is 4 to 5 modern semi tractor trailer combos transporting a dismantled b-17 to be restored. I know there will be 1 for the fuselage, 2 for wing components and 1 for misc pieces like the engines and crated components.

I am not a scholar of model kits, but reviewing the major on-line resources such as oldmodelkits.com, scalemates.com etc.,
I dont think I am going out on a limb to say you are out of luck. Only a few 1:64 scale aircraft kits were ever produced, a long time ago.
Now if you could settle for 1:72 scale engines, which would be about 11% under-scale, a world of aftermarket resin parts lies open before you. Search for Aires to start with.

Thanks, I know my research rendered me 2 different kits in 1:64, both by Lindburg, the B-17 and a HE-111, the B-17 had 5 or 6 different box and decal variations that I have found but are not the best when it comes to detail although one will be the core of the load build.

There was also a B-25 Mitchell by Revell in various versions.
https://www.scalemates.com/kits/265469-revell-h-238-b-25-mitchell

I havent been able to find any pictures of the contents.

I may just bid on one of them on e-bay, just to have it, I know there were a few little private single and twin engine puddle hoppers at one time also. I believe Aurora made the kits.