What he said. You'll have to modify your 250 bracket.
Cut the bracket and weld in a section to allow for the extra height of the 292. It should share the two thermostat housing bolts that are just below the upper bypass nipple. You'll need longer bolts. The bracket should also use the threaded hole that is on the top side of the head, just above the first manifold stud. You'll have to grind away the front of the bracket to clear the bypass hose. If I remember correctly, the back side of the bracket was fairly massive. I trimmed a lot of that away to clean it up and also to clear the tube type headers.
Before you weld the bracket up, you need to get a handle on what you are going to need for pulley and belt alignment.
I mixed and matched different pieces to get my setup and it may not be what you want. My crank dampener pulley is a two groove that lines up with a two groove alt pulley. The back belt is crank to alt only. The second belt is crank to water pump rear groove to steer pump to alt(just barely) and crank.
I have a single pulley on the front of the balancer that lines up with the front water pump pulley groove and will someday go to an AC pump. I've been saying that for a year and a half. darn. Someday. Today I'm knee deep in Corvair engines in various stages of disassembly. I just need to change that to "various stages of assembly". It grew from a single 140HP with 4 carbs, to a 180HP Turbo to another 140, to a twin 3BBL Weber engine, to a twin 1BBL 110HP engine and an extra set of 140 heads. Good thing I only have two cars.
Hope this doesn't bother anyone.
They ARE six cylinder, Chevy, and pre '73. I even have thoughts of getting a Corvair pickup truck to put one of the engines in.
