Donor vehicle questions

[67pete300]

So I've been casually looking for a 5.3/4L60e drivetrain for my 65 C10 while chipping away at smaller projects. Despite their ubiquity, they don't show up as parts on craigslist very often and those that do often seem sketchy in that they are not complete with all the accessories and have unknown pedigrees and mileage.

EBay and other drop out packages from retailers seem pretty darn expensive and shipping will be an expensive adventure. Easy $2500-$3k for a garden variety LM7/4L60e.

So I've been considering buying a whole donor truck or van locally and have questions. Cost and completeness are big considerations.

1. I think I want a LM7 5.3 for a solid upgrade without the extra cost of the 6.0. But the 4.8 hp/tq numbers are not too different from the 5.3 and it could open the trade space and save money. Is there a noticeable difference for a dead stock swap into my shortbed C10?
2. I don't think I want a 4L80e because I'll have to swap to a high hump. Should I worry about this too much? The van options are 2wd while most trucks are 4wd, but many of the vans are heavy duty with 4L80s.
3. I think there are differences in the van accessory mounting (than a truck) but I'm not sure what they are and if they are a factor. Is a van a good donor?
4. Model years: I think I am looking for a 2000-2005 ish truck donor or a 2003-2007 van. Presumably newer means lower miles but the newer models have more sensors and electronics to disable.
5. Mileage. Something between 150-200k is probably realistic. Should I assume that I have to rebuild the 4L60e for this type of mileage? That factors in the economics.
6. Extra stuff: Obviously with a full donor vehicle I'll get all the ECM, harness, pedal and accessories. Can anything else be used like the radiator and/or fans, wiring/connectors, driveshaft, etc?
7. I might be able to get some salvage value out of the rest of the donor once I've picked it over. Some vans come with ladder racks and interior storage that is valuable.

I'm looking for a donor vehicle in the $2500-$3k range. Is it worth it? Or should I just suck it up and order a complete package from a parts retailer?

If anyone has any suggestions for sources in Northern Virginia/Maryland, I'm all ears.

Thanks for your feedback.