Sweet! I love those 406's. That is not a bad price at all. I've seen complete rebuilt 406's go for double that. The 406 was a 62 1/2 till 63 1/2 only deal. It has the same 4.13 bore as the 428 but uses a 3.78 stroke crank. If it's original it should have grooved main journals on the crank. The cross bolts were likely added later at some point in it's life. The blocks were cast with the crossbolt bosses in place and some 406 blocks have very thick 427 walls and all have enlarged
oil passages and
oil pressure relief valves. It should be a solid lifter block and you will see "HP" cast on the side and rear of the block and also inside by the cam and main bearings. If it does not have the "HP" it's not a true 406! They also sported lowriser heads and intake with some using the 3x2 tripower setup. HOWEVER some guys will bore a 390 .080 and call it a 406 so take a good look. Get the casting numbers and date code off the block and heads and let me know what they are. The block should have the older 2 bolt motor mounts also. The last 406 I saw on ebay was close to $4000 but the guy shilled the bid being greedy. Nice find! G.