First of all, unless this Escort is a 1999 model the guy is crazy. The 1970 truck was built to last while the escorts in the Pacific NW can be had for $200 at most towing auctions.

You really need to fill us in on more info. about both cars though. What year is the escort, how many miles are on both? What area of the country have these cars been?

The Kelly Blue Book won't really give you an accurate picture on something so old but it does help. At this age, the condition of the truck is really important.

Don't do it!! You'll appreciate the truck for many years to come if you put some dollars into it and make it nice.