valley sealing help!

Ive ran into a little dilemma, i'm starting to mock up my engine to check clearances and fitment, and i notice something about the valley pan gasket.
i have a set of fully ported 452 heads and with the valley pan gasket on the engine the height of the gasket is .050 shorter than the intake runner. if i trimmed the gasket that much i don't think it would seal. i THINK my only other option is to get the valley plate from 440 source to fit a 383 block and these intake gasktes then silicon them to the plate. http://www.hughesengines.com/Index/...Q==&searchmode=partnumber&page=2&partid=23711

any opinions?