I do see a 3994258 for a 292 block 1963 - 90 (not 8994256) .
Yes, a 292 will be taller and if you are running a downdraft carb & stock air cleaner there wouldn't be clearance with a stock hood. As you noted the motor mount & fuel pump locations are switched on a 292.
Does the dipstick go straight into the pan rail (62-67), or does it enter the block a little higher and on an angle (68-on). Or is a Chevy II forward sump with the dipstick going into the block adjacent to the distributor?
easy ..... look on the 'pass' side of any (late model) chev Six .
u'r looking at the "Lifter / Side Covers" : 250 motor has 4" side covers.
292 motor has 6" side covers , you CAN TELL , that's what makes a 292 engine a " TALL DECK " motor
(like 1 1/4" taller).
yes ----- there are some other differences : pass - side
"fuel pump" & pass - side " motor mount" are switched position ..... but, that's easy. 292 oil pan IS bigger ,
and, most 292's have a
"Huge crank Ballancer" ...... which makes the engine 'measure longer' , for clearing your radiator.
Most of the time, you just run an "electric fuel pump" , and, change the "pass side motor mount"
.... your golden.
(I have pictures of each engine)
If you were installing a 292 in a 3rd GEN ..... it will be ALOT easier, for more room in the engine bay.
Post a picture of u'r motor --- on the 'pass side' (side covers).
later , jim