Thank you all for the great info, defiantly appreciated!

I got the 455 the other day and, it barely turns 90 degrees then stops. I pulled the plugs and cylinders 2 & 4 had rust on the plugs so I'm soaking all the cylinders with MMO and wd40. Hoping it comes around! I didn't get a chance to pull the heads yet but, the casting on them says "5" and that it, i can't find any info out there that in '74 they used a "5" casting number, the secondary casting is 16, any ideas on what heads these may be? I'll get pics soon.

My plans for the 455 is to at least get it up and running and run it for a few years until i can afford to have it gone through and put some better parts into it.

I am definitely going to keep the 350 around until i know for sure the 455 is a runner, good idea unconn86hgiv!

Thanks again everyone!