1952 Chevy Pickup build help

[Thp_Stang]

I have a 1952 Chevy pickup, I presume it's a 3100 but haven't looked up the vin info yet, and I'm going to be starting my restoration/build in July or August and have been stumped on some info. I've found a motor and transmission setup that I'm going to use, and I need some help figuring out how to do the swap. The motor and transmission that I'm using is a 4.8L Vortec and a NV4500 5 speed out of a 99+ Silverado 1500, and I need to find some motor mounts and a cross member that will work with the setup.

However.... the problem I've run into is that when I first got the truck I was told that it was sitting on a 1974 K5 Blazer frame, but I just found out by some frame research that it happens to actually be on the stock frame, or at least a 52 model frame. Now this wouldn't typically be an issue except for the fact that the front and rear ends have been taken off of the 74 Blazer as well as the 4x4 system, so the cross member and motor mounts that I found to work with a 74 Blazer are for, of course, the 74 Blazer frame and not the 52 frame.

The cross member is the Pacific Fabrication LS swap cross member for the 70 model Blazers, and the motor mounts are LS mounts made for the Blazer... I'm not sure what the difference in the width of the frames are, but I was thinking about ordering those mounts and the cross member and then just cutting, or welding where it needs it since I know it will clear the suspension on the front end, if it matters. If anyone could help me figure out what I need to do, or what parts I need to get I would greatly appreciate it! This is my first build, so I'm not sure what all I need to do.