you said it had a 370 rear end, is that a Datsun rear end or did he swap a solid rear axle. Also, the Dart 2.02 heads are almost a grand by themself if they are aluminum. If he has solid lifters than he running a rather aggressive cam and valve adjustments are something you will need to learn to do. Not hard, but it is maintenance that will be required. Roller rockers are just par for the course with a large cam, no biggie there. You need to find out if they are 1.5 or 1.6 rockers for future use if you buy it, so you can more accurately calculate lift. Lets see, buy the looks of the accelerator pump diaphragm in front that is a Holley carb. Not sure if it is a double pumper without looking at both sides of it. He is running an MSD box on it, what kind of distributor does it have? An HEI GM one or an MSD one? Not the worst built 350 by his numbers, but you would need to know more about the pistons, name brand, rods, crank, cam size, etc. Are the heads aluminum or iron? THe carb is not hard to work on at all. Holleys can be tuned with great ease. And they are dirt cheap to replace. Not the best carb for fuel efficiency, but for power, they are awesome. I grew up working on Holleys all day long. I can rebuild one blindfolded. Keep one thing in mind, you will be purchasing a car that will require lots of maintenance. You have no idea of the quality of the swap, or the wiring. Be prepared to have to redo somethings. I think 5500 to 6000 is not out of the question for this car. Maybe as high as 7000 since the body appears straight by the photos, but without closer inspection I will give him the benefit of the doubt.