Snowman, One thing I have mentioned before. Not sure if the SPA manifold will fit into your chassis with a 250. The turbo will probably conflict with the steering shaft. There is a 292 in mine with almost the same chassis (mine is a chevy, yours is a buick) but still nearly the same chassis. My turbo is within 1/4" And has rubbed at some time because it leaves marks on the shaft. With a 250 being much shorter than a 292, this is going to put the turbo into a big conflict.
